Rare Aircraft – Messerschmitt Bf.108 Taifun (rewrite)

By me

Author’s note: while not a new topic per se, the Bf.108 has turned out to be quite a popular item on this blog, with my previous post rising to an all time high viewcount. In view of that – and my “temporary”, two-year-old promise to finally sort out the post’s missing images – I’d decided I might refresh it, and post it in a format consistent with the new look of this site πŸ™‚ .

When the first Bf.109s faced their German rivals in mock dogfights in the mid 30s, few observers – in any country – were left in doubt about the capability and raw potential of Messerschmitt’s first fighter design. International flying competitions during the run-up to WW 2 had only confirmed these impressions – but it would take the type’s impressive (though in later years somewhat diluted) wartime service record to finally remove all doubt. Lasting more than a decade in one form or another, the type’s all-up production run had encompassed more than 35,000 examples, spanning everything from the prewar lightweight Bf.109B Berthas to the post-war Merlin-engined Hispano Buchons.

A very advanced design by contemporary standards, the Bf.109 was not actually ground breaking per se; when all was said and done, it had not really introduced anything new or revolutionary into world of interwar fighter design. Rather, what it did – and did brilliantly – was to combine all the cutting edge technologies available at the time into a single aircraft: the monoplane configuration with its high wing loading; the powerful liquid-cooled V engine and its variable pitch prop; fully retractable hydraulically-actuated landing gear; the enclosed cockpit…

Other design features – which soon became the type’s hallmarks – had also included automatic leading edge slats and an innovative construction technique that had made the aircraft extremely light by the fighter standards of the day. The latter had also made the 109 simple and cheap to build, quick and easy to service – and especially tough, durable and reliable under actual combat conditions (though the rigors of the Soviet campaign would put its mettle fully to the test). And while the big engines and retractable landing gear and the monoplane configuration could easily be traced to some of the eminent fighter aircraft of the era, the above features were inherited from a decidedly more peaceful source – the lowly Bf.108 tourer πŸ™‚ .

Messerschmitt Stiftung’s gorgeous Bf.108B-1 sporting accurate period colors (photo source: http://www.aviation-ancienne.fr)

When I grow up I want to be a fighter!

The aircraft that would eventually lend its technical solutions – not to mention most of its airframe – to the Bf.109 had started out in life as the four-seat* M.37 tourer prototype of 1934. Designed by the young Willy Messerschmitt, Bayerische Flugzeugwerke‘s chief designer, the M.37 was conceived primarily to compete in the 4th Challenge de Tourisme Internationale being held the same year. This interesting – and I’m sure sorely missed – general avation competition was intended to promote and spur the development of light touring aircraft, and had included such competition categories as “Short Takeoff”, “Short Landing”, “Fuel Consumption”, “Minimum Speed”, “Maximum Speed” and “Technical Trial”. Topped by an (at the time) grueling and arduous 9,500 km rally across the diverse spaces and climates of Europe and North Africa (stopping also in Zagreb πŸ™‚ ), this competition was intended – much like the 24 Hours of Le Mans in the automotive world – to weed out inferior designs and encourage quality solutions for future touring aircraft.

* though designed as four-seaters, the M.37 and the early Bf.108 were actually flown as two-seaters, with the rear seats permanently removed to provide some storage space. With virtually all pre-series production versions having been used for competitions and proving flights, this gave impression that they were designed outright just for two…

Based in part on Messerschmitt’s previous M.29 tourer – designed in a similar manner for the 1933 competition, but never taking part due to a spate of crashes – and the M.35 aerobatic trainer prototype, the M.37 was a sleek and elegant all-metal, stressed-skin low-wing monoplane, sporting retractable main gear, an enclosed (and heated) cockpit, full-span flaps – with roll control provided by roll spoilers (in 1934!) – and a variable pitch prop… all of which had immediately made it stand out like a sore thumb in the wood & fabric biplane crowd of the time πŸ™‚ . This brazen level of unorthodoxy had continued under the skin as well, with the wing being built around only one spar – a design that was made to work thanks primarily to Messerschmitt’s extensive glider building experience gained during the restrictions of the Versailles Treaty. The innovative mechanical leading edge slats could be extended manually to improve the airflow over the wing’s outer sections – which were likely to stall first – reducing the stall speed to just 61 km/h (33 knots). This in turn helped to significantly shorten the aircraft’s take off roll – not to STOL levels, but not far above either – and dramatically increased low-speed maneuverability, handling at high Angles of Attack, and behavior in, during and after a stall.

The leading edge slats on a production Bf.109. Interestingly enough, the slats were a British innovation, patented by Handley-Page several years prior their use on the M.37. To use them, Willy Messerschmitt had traded in his own patent, the single-spar wing (photo source: German Bundesarchiv via Wikimedia)
As with the wing, the whole design philosophy was to make the aircraft as simple as possible, using the fewest realistic number of parts needed to make a light and durable airframe. Pure functional minimalism. And it had worked, and worked well – compared to similar designs of later dates, the M.37 was indeed among the lightest and best performing. Official flight testing prior to the 4th CdTI was marked by the general enthusiasm of all pilots that had flown it, prompting the German Aviation Ministry – the Reichsluftfahrtministerium, or RLM – to give the aircraft a tentative green light as the Bf.108*.

* of note here is the oft-confused and misinterpreted designation. Popularized by the 109, the “Bf” prefix stood for the initials of “Bayerische Flugzeugwerke” (itself often shortened to BFW); however, when the company was renamed to “Messerschmitt Flugzeugwerke” in 1938, allΒ subsequent designs were given the new “Me” prefix. The designs that had been produced before the name change had retained their original prefixes through the war – so there never was an “Me-108” as is claimed by some Internet sources.

However, despite the praise and the design’s undoubted qualities, one feature of the 108 had never really sat well with some of the test pilots: the roll spoilers. With the full length of the wing’s trailing edge taken up by the flaps – which increased the wing area by a significant 8% when fully extended – there was no space for traditional ailerons; roll control was instead provided by roll spoilers located on the wing upper surface, whose extension would create a difference in lift along the span of the wing. For example, if you had wanted to roll left, the spoilers on the left side would extend, dumping lift on that part of the wing. The wing’s ride side would now be producing more lift, which would roll the aircraft left around its center of gravity in the same manner as the ordinary aileron. This was fine in theory – and is today still used to provide additional roll control on a number of civil and military designs – but back in the 30s it was viewed with suspicion and more than its fair share of antagonism. This came to a head when test pilot von Dungern was killed while testing the spoilers, presumably somewhere near the edge of the envelope.

With the RLM’s well documented dislike of Willy Messerschmitt threatening to ground the Bf.108 – like it had the M.29 a year before – there was no other option but to revert to a conventional aileron arrangement. “Conventional” though should be taken with a grain of salt when Willy is concerned, because the resulting arrangement had still managed to raise an equal number of eyebrows… πŸ™‚

You can see that Messerschmitt was adamant with his high lift devices: shortening the flaps a bit, he just managed to squeeze in two small 30 cm wide ailerons, lengthened to compensate for their lack of span. Note also the upper tailplane bracing that would be removed on production versions. The aircraft pictured here was one of four intended for the 4th CdTI – and one of three to actually compete – wearing its race number “11” (photo source: http://www.network54.com/forum)

In this form the aircraft became known as the Bf.108A, the designation under which it would be entered in the competition. Sadly, its beautiful handling and avantgarde features did not really help its case there, with the far lighter, nimbler and simpler wooden biplanes wiping the floor with it for most of the competition…

However, the 108 did eventually notch up several notable wins, all of which would eventually steer its development into the aircraft we know today. The top three aircraft in the “Fuel Consumption” category for example were all 108s – with the winner registering an impressive 10 kg (14 l) / 100 km. This figure – nowadays exceeded even by a basic SUV – was made even more impressive by the fact that the 108A was not powered by a small, frugal, fuel-sipping engine, but a 220 HP Hirth HM 8U inverted V8 (a proper GA engine πŸ˜€ ). Its power and torque had also helped in the “Maximum Speed” event, where the 108s again took the whole podium, with the slowest – at 283 km/h (153 knots) – being 30 km/h (16 knots) faster than the next contender. The trans-European rally was less of a success though, with the 108’s best result posted by Theo Osterkamp, who placed fifth. However, this poor showing was more due to the scoring system – and external influences such weather and poor navigation – than any faults with the aircraft themselves. Points were awarded based on total average speed, BOTH moving and stationary; this had meant that a fast aircraft grounded by weather for extended periods would score less points than a slow aircraft that had managed to evade the worst of it and continue flying. When everything fell in place though, the 108s had regularly posted the fastest average flying speeds – including on the legs to and from Zagreb πŸ™‚ .

In the end, when the tally was done, the 108s had placed 5th, 6th and 10th out of a grand total of 19 contenders. But more importantly, their demonstrated low fuel consumption, high cruise speeds and beautiful handling – not to mention a leather upholstered and heated cockpit! – had immediately lent them well to cross-country touring. A clean, aerodynamic airframe, able to zip along on comparatively little power – sounds much like the Lancairs and Cirruses of today, doesn’t it? πŸ™‚

Another quarter view of “11”. The early pre-production Bf.108As were the only models to sport the three-bladed VDM propeller (photo source: http://www.network54.com/forum)

This did not slip past the cash-strapped BFW, where Messerschmitt had decided to capitalize on the type’s competition success by adapting it for series production. To this end, a batch of pre-production Bf.108B-0 models was made (though they were still commonly known as the Bf.108A), with each successive aircraft representing a slight step toward a definitive production standard.

By 1935, these aircraft had already started making a name for themselves – some quite literally πŸ™‚ . Well established as the fastest tourers in the sky, one example was chosen by famous German aviatrix Elly Beinhorn for her record breaking flight from Berlin to Constantinopole (now Istanbul, Turkey) and back. Her little Bf.108B-0 had more than lived up to its Taifun nickname when it took just 13 and a half hours to do the 3,470 km trip, flying along at an average ground speed of 257 km/h (139 knots) – a respectable result even by today’s standards.

Ms. Beinhorn and “Taifun” posing after their long flight. Easily seen here is the A/B-0 models’ bathtub cowling for the Hirth engine (photo source: http://www.luftarchiv.de)
Like most 108s of the era, “Taifun” – the exact aircraft illustrated here – wore this simple gloss white paint scheme for its record flight (photo source: http://www.aviation-ancienne.fr)

This very convincing – and, at a time when the nation was hungry for records, very public – success had immediately opened the floodgates, and the 108’s already significant popularity skyrocketed overnight. As was the case with its showing at the 4th CdTI, this had not gone unnoticed at BFW, where Willy Messerschmitt increased efforts to finalize the Bf.108B-0 into a definite, production, high performance cross-country tourer. The end result was the Bf.108B-1, now adopting Taifun into its official name πŸ™‚ .

Ms. Beinhorn posing in an early-production Bf.108B-1, sporting the type’s distincive logo (photo source: http://www.ctie.monash.edu.au)

While there was nothing really wrong with the original A series (and the early B-0s) performance-wise, they did have several features that were judged to be unfit for a production version. The whole idea behind the B-1 was to make the aircraft more production- and consumer-friendly, so the first item to go was the original’s powerplant. The expensive and hard-to-come-by VDM three-blade variable-pitch propeller was replaced by a simpler and cheaper two-blade fixed-pitch prop (although Messerschmitt’s own P7 variable-pitch unit was offered as an option), while the HM 8U engine was swapped for the more readily available Argus Ar 10C inverted V8, producing 240 HP. The wing was a bit dulled down as well by a reversion to a fully conventional aileron and flap arrangement – but had compensated for it by gaining a folding mechanism that allowed it to be tucked close to the fuselage for easier transport by road and rail.

Additional minor changes included the removal of the upper tailplane bracing mentioned previously, the replacement of the next-to-useless tailskid with a non-retractable, freely castoring tailwheel, and the shortening of the glazed canopy over the rear seats.

In this shape and form, the aircraft had continued to participate in international competitions, rallies and fairs (and, most notably, the 1936 Summer Olympics in Berlin) – but now under the increasingly ominous banner of Nazi propaganda. Indeed, soon after its initial competition successes, the fast-growing Luftwaffe had started eying the 108 as a liaison and communications aircraft to replace the obsolete, lumbering biplanes then being used.

A Bf.108B-1 in a prewar civil scheme, showing off some of the changes from the A model. Note the shallower, oval cowling, the modified canopy and the tall tailwheel (photo source: http://www.network54.com/forum)

However, the 108’s biggest contribution to the Wehrmarcht’s war effort was as the basis and jumping-off point for the impressive Bf.109 – a fact that in itself further underscores the essential quality of the Taifun’s design. In a fantastic display of lateral thinking, in 1934 Messerschmitt had simply taken the plans for the 108A and modified the design into a single-seater with a narrower fuselage, a big V12 up front – a “right way up” Rolls-Royce Kestrel on the first prototype (oh, the irony πŸ˜€ ) – and some firepower in the slightly modified wings (which too had reverted to a conventional aileron/flap arrangement). Apart from other smaller changes needed to fit all of this together, the rest of the new aircraft was a straight 108 πŸ™‚ .

Neatly showing off its 108 lineage is the third Bf.109 prototype – the Bf.109V3 – which had also served as the starting point for the B family (the type’s first production series). Apart from the complete tail unit, the 108’s DNA was also evident in the pilot position, which was exactly where the 108’s rear seats would be. Also not the cut-off spinner, a nearly design feature to facilitate the installation of the nose canon (photo source: www.network54.com/forum)
A production-standard Bf.109B of the Legion Condor during the Spanish Civil War. The coolant and oil radiators on these early versions were mounted under the nose, giving this version a clearer 108 lineage (photo source: http://www.hrvatski-vojnik.hr)

While the wildly differing roles of these two aircraft may have raised some eyebrows – not to mention questions about Willy Messerschmitt’s command of his senses – the 108 was actually an amazingly suitable base for the 109. The Taifun’s advanced construction meant that the 109 could be light and maneuverable – as was demonstrated on more than one occasion over the next decade – and its relatively low part count meant it was simple to maintain and repair in the field with whatever facilities were on hand. Lacking complicated construction components also meant that it was very tolerant of combat damage, and the low number of critical design points made disabling it with a “lucky shot” quite the enterprise. At the same time, the clean airframe sliced through the air with relative ease, meaning the 109 could do with relatively little power and a smaller, more economical engine – quite a welcome feature given its notoriously short range and pitiful combat radius.

Achtung… Messerschmitt?

But an interesting and varied operational history was not just the prevue of the 109. Having had the (mis)fortune of being the most advanced light aircraft in the world during a period of significant – and often rapid – political changes, the Taifun had naturally accumulated its fair share of odd operators. Apart from the “usual” Axis users such as Bulgaria, Romania and Japan, there were also a few unexpected ones like China – and the Royal Yugoslav Air Force. The dozen or so B-1s acquired in 1939 were part of a larger batch of aircraft that had also included 60 Bf.109Es and quantities of spare parts – all paid for not with actual money, but in strategic materials such as iron, copper, aluminum and coal… materials abundant in the Kingdom of Yugoslavia, but scarce and badly needed for the military buildup in Germany.

And while the 108s would go on to lead rather uneventful lives in training and liaison roles, the 109s would pretty soon enter the history books πŸ™‚ . The most potent fighter aircraft fielded by the Royal Yugoslav AF at the time of the German invasion in 1941, these machines would go down in history as the only 109s to ever face other 109s in outright combat, clashing violently during the spirited – but ultimately futile and short-lived – defense of Belgrade.

Ε -08 (Ε  for “Ε‘kolski”, literally “training type”) at an airfield that could very well be Borongaj or Lučko (photo source: http://www.network54.com/forum)
Yugoslav 108s were well known for their interesting paint schemes, with the above camouflage pattern being the most prevalent (photo source: http://www.network54.com/forum)

Next on the scale of the improbable was – the US military πŸ™‚ . While it was quite common for the USAAF to fly and evaluate captured Axis aircraft, the single Bf.108B-1 it had operated had never even left Germany – and was actually peacefully bought, rather than forcefully captured. Designated the XC-44, this interesting aircraft had been based in Berlin and used as a high-speed staff transport by the US Military Air Attache up until 1941, when it was repossessed by the German government following the United States’ declaration of war against Germany and its allies.

Quite possible one of the rarest – and most ironic – paint job ever applied to an in-service Messerschmitt! (photo source: http://www.network54.com/forum)

Equally improbable – and, if anything, even more interesting – were the four Bf.108B-1s brought into the UK before the war. Bought on the “open market” just like the XC-44, but operated by civilian users, these examples were quickly impounded and pressed into RAF service at the start of hostilities, becoming the Messerschmitt Aldon. Used – like contemporary Luftwaffe examples – in the communications role, they were capable of comfortably outrunning every liaison type in the UK – though their shared family tree with the Bf.109 had often caused identification problems among defending fighters…*

* for those wondering how could the 108 be so easily mistaken for the obviously different 109: the first of the Griffon-engined Spitfires, the Mk XIIs, had been delivered with clipped wingtips intended to improve roll rates and increase maximum speeds at lower altitudes – a feature already well known at the time, and seen on virtually all Spitfires marks since the Mk V. On the ground, the Spit’s famous elliptical wing planfom was still very much obvious; up in the air however, things were somewhat different. On their first few sorties, only the mark’s new-found speed advantage had kept it safe from the attentions of patrolling Hawker Typhoons, which had mistaken their long noses and cut-off wings for those of attacking 109s…

A rare photo of one of the four Aldons – a shape that really is not difficult to confuse with that of the 109 in the heat of combat (photo source: Wikipedia)
The 108 does ineed look striking in RAF camo colors! An interesting feature of this scheme is the bright yellow underside: even more so than from the sides or top, from the bottom the 108 can be virtually indistinguishable from the 109 when viewed from a distance. So to prevent the Aldons from being fired upon by nervous AA gunners – who may or may not have noticed the RAF roundels – it was considered prudent to make them as visible as possible from that angle… (photo source: http://www.network54.com/forum)
Another catchy scheme – which again didn’t help much with identification (photo source: http://www.network54.com/forum)

The postwar period too saw its share of unusual operators, including Czechoslovakia (where the type was known as the K-70), Poland and even the Soviet Union, all of which had flown examples captured during the final days of the war. Another interesting operator – well known now for their very colorful 108s – was Spain, which had acquired several batches of the type during the Spanish Civil War and Franco’s subsequent ascension to power.

For the full photo history of the 108’s civil and military service around the world, you can visit the excellent pages below, a gold mine of fantastic information from which I’ve linked many of the photos above πŸ™‚ .

Western promises

Unlike its armed cousin though, the 108 did not go through new versions like pairs of socks. Apart from the B series, there was only one major production version, the D; equally, experimental and test versions were also few in number. However, what the latter lacked in quantity, they’d definitely made up in quality… πŸ™‚

By far the most normal – and sensible – of these was the Bf.108C-1, an ungainly 1936 modification that had seen a B-1 airframe refitted with a Siemens Sh 14A-7 seven cylinder radial. Coupled with its increased frontal area and drag, the engine’s rather pitiful 160 HP – 80 HP, or 33%, less than the type’s standard Argus Ar 10 – made for some appalling performance, which saw the aircraft remain a one-of. However, while this version seems to be an unnecessary step backwards, there appears to have been some method in Messerschmitt’s madness after all. While there’s little concrete technical info available on the mark, the C-1 was most likely an insurance policy for the event that Ar 10 production became disrupted or sidetracked to other more important projects – a policy not unlike that later employed by Avro with the Bristol Hercules-engined Lancaster B II.

Used solely for promotional purposes during the 1936 Winter Olympics, the C-1 had managed to clock 21,600 km without incident, shuttling film roles of the games between Berlin and Stockholm. Abysmally underpowered, the aircraft was later re-engined back to the standard Ar 10 (photo source: http://www.network54.com/forum)

At the other end of the spectrum was a stillborn version that some sources also label as a C-1 – which, given the German aeronautical industry’s policy of reusing designations of failed models, was entirely possible. Diametrically opposed to the Siemens-engined version, this C-1 was to have been a high-speed model, fitted with a Hirth HM512 inverted V12 that would have developed an astounding 400 HP on takeoff! πŸ™‚ Ground testing in 1938 though had quickly revealed that noticeable airframe vibration and buffeting was to be expected above 325 km/h, which would progressively become so severe that it could even tear the airframe apart. Given the scope of engineering changes that would be needed to make this version work – and the impending shift of the German military industry into high gear – meant the project was quietly dropped…

That the only way was up was quite literally demonstrated in 1939 by a specially-modified high-altitude Bf.108B-1 (lacking a special designation), built to capture the world altitude record for its class. Fitted with a supercharged Hirth HM508 inverted V8 producing 270 HP – and also providing air to pressurize the cabin – this aircraft had reached an impressive 9,125 m (29,930 ft) in the hands of Hirth’s managing director, Herman Illg.

Series production models were however less interesting – and had pretty soon started suffering from an acute case of Skyhawk-itis πŸ˜€ . If you took ten C172s of the same model and same production year and lined them all up, you’d be able to spot – with very little effort – at least one difference or unique feature on each aircraft… a different landing light here, a static port moved to there, a panel layout tweaked just so… and so on. As production ramped up, the Bf.108 became no different, with options and features freely flowing between versions. This had made sorting them by model a bit difficult and vague; however, after roving the Internet far and wide, I think I’d managed to hit the nail on the head in general terms:

  • B-1: the already-described base model
  • B-2: generally very similar, but with the wing fold system removed and the variable pitch P7 prop – offered as an option on the B-1 – fitted as standard. This version could easily be recognized by its thinner prop blades and slightly different propeller hub
  • D-1: debuting in 1941, this was the first model produced outright for military use, and had featured a modified vertical stabilizer, improved fuel feed system, more powerful electrics, a windscreen wiper and a new constant speed prop, being turned by an Ar 10R engine of the same power output as the C (of note here is that “variable pitch” and “constant speed” propellers are not the same thing. A constant speed propeller – standard today – automatically varies the pitch of its blades to maintain the same RPM regardless of throttle setting; the variable pitch prop however was fully manual, with the pitch having to be readjusted with every change of throttle or airspeed. The 108’s variable pitch prop was operated by a large circular handle in the middle of the panel – known among the type’s pilots as the “coffee grinder” – and had added quite a bit to the crew’s workload)
A fine photo of a B-1 fitted with its original fixed pitch prop. Somewhat rare even in the 40s, a majority of these versions were later refitted with the variable pitch P7 – though at least one surviving example, D-EBFW, had retained the original well into the 2000s (photo source: Flickr.com, user “kitchener.lord”)
The more common P7 fitted to Messerschmitt Stiftung’s Bf.108B-1. In this guise, the B-1 was externally indistinguishable from the B-2 (photo source: Wilbergair.com)
Photos of “proper” D-1s are nigh impossible to find, so I’ll just have to improvise a bit… the mark’s most distinctive feature was the “crowned” spinner for the new constant speed system, beautifully modeled here by a B-1. Like the P7, this unit was eventually retrofitted to some examples of the B-1 and B-2 (photo source: http://www.ampa.ch)
Not much quality-wise, this was the best photo I could find that nicely shows the D-1’s other unique structural feature. Dispensing with the rudder horn balance seen on the B series, the D-1 used a slightly modified counterweight arrangement that was supposed to give slightly more rudder authority and better stability. Also note the B-1’s fixed pitch prop; whether this aircraft had actually been produced with it, or had the unit been fitted later, is unknown (photo source: Wikimedia)

The D-1 would also signal the last of German Bf.108 production before the whole works were transferred to France at the beginning of 1942. In a bid to free up domestic production capacity for badly needed Bf.109s, the B-2 and D-1 were allotted to the factory of the SociΓ©tΓ© Nationale de Constructions AΓ©ronautique du Nord – SNCAN, or simply Nord – just outside Paris, where they would remain until the end of the war in France – with interesting consequences.

Following the country’s liberation in the summer of 1944, SNCAN – having produced just 170 aircraft out of the type’s total production run of about 880 – found itself with a significant number of uncompleted airframes and engines. Deciding it would be a waste to just throw them all away – and desperate to gain a foothold in the country’s recovering economy – the top brass elected to restart production of the 108 in the guise of the Nord Pingouin (what a demotion – from an impressive meteorological phenomenon to a cute polar animal πŸ˜€ ). The first model, the 1000 Pingouin, was virtually identical to the Bf.108B-2, save for the reintroduction of the B-1’s folding wings and the refitting of the D-1’s improved vertical stabilizer.

Apart from a French scheme, there was little to distinguish the early Pingouin from a regular Bf.108 – or rather from the smorgasbord of version features the late-war models had become (photo source: http://www.network54.com/forum)

Once these stocks had been exhausted, it was a relatively straightforward matter to re-manufacture the airframes from the original plans, the WW 2 production tooling having already been set up and waiting. However, the engines had proved to be a bigger challenge, having been produced in – and imported from – Germany during the war. The only way around this was to use a local engine of similar power; but the only unit available was the Renault 6Q family of six cylinder inverted inlines, a powerplant considerably longer than the compact Ar 10. But having no realistic alternative, SNCAN went ahead with the redesign, creating the long-nose 1001 Pingouin I. Powered by the 233 HP 6Q-11, this model was quickly followed by the 1002 Pingouin II, which upgraded to the slightly more powerful 240 HP 6Q-10 – and which would eventually become the most common of all the Pingouins.

These would eventually number at 286, bringing the 108’s overall total to a tad over 1,100 aircraft. However, I was unable to confirm with absolute certainty when French production had actually ceased – but given the type’s low rate of production, I’d guesstimate the aircraft had disappeared from the production lines during the early 50s.

One of the very few airworthy Pingouins still using the Renault engine, this handsome 1002 is seen sporting a prewar 108 paintscheme of the type worn during aviation competitions of the 30s. Note the extended nose for the long, but comparatively narrow, 6Q (photo source: http://www.airventure.de)

Note: some of the surviving aircraft have since been retrofitted with standard Lycoming and Continental engines, and have shorter, broader and more oval cowlings. For the sake of simplicity, I decided only to represent the original Renault-powered models here.

A (third) leg to stand on

However, the end of the Pingouin was not the end of France’s 108 connection πŸ™‚ . Back in 1943, SNCAN – under prompting and guidance from Messerschmitt – had started working on an experimental tricycle version of the Bf.108B-2, which would have been known as the Me-208 (since this version was conceived after the creation of the Messerschmitt Flugzeugbau, it was allocated the Me prefix). Two prototypes were built during the last days of the occupation of France, but only one would actually survive to its end, later to become known as the Nord 1100 Noralpha. As in the case of the 108, SNCAN had decided to see the design though to the end – having already done 90% of the work – and market it under its own name. The result was the 6Q-10 engined 1101 Noralpha (known in French military service as the Nord Ramier, or “dove”), whose production ran to the 205 mark.

One of the surviving Noralphas in a tipsy landing. Though very similar to the intended Me-208, the design was already starting to significantly depart from the clean lines of the 108 (photo source: http://www.flugzeuginfo.net)

Much like the 108, the Noralpha did not see much in the way of different versions, but had compensated for it by a history of use as an engine testbed πŸ™‚ . The first (rather conservative) iteration was the planned, but never built, 1102 Noralpha II, which would have been powered by the 6Q-11 seen on the Pingouin I. This version was followed by the slightly more successful 1104 – which had actually made it to the prototype stage, but no further – powered by a Spanish Potez 6Dba engine of the same configuration and power output as the 6Q-10.

However, the ultimate expression of power – and arguably of the entire 108 line – came in the form of two 1959 SFERMA-Nord 1110 Nord-Astazous. A project of the equally long-named SociΓ©tΓ© FranΓ§aise d’Entretien et de RΓ©paration de MatΓ©riel AΓ©ronautique – SFERMA, a company formed in 1949 for the purpose of repairing and overhauling civil and military aircraft – the 1110s were conceived as testbeds for the in-development Turbomeca Astazou turboprop. The first example started out in life as the 150th 1101 Ramier produced, and was initially fitted with the 467 HP Astazou I. A bit later in the program, this aircraft – along with an additional 1101 – was re-equipped with the more powerful 550 HP Astazou II, as well as a host of other modifications including shorter span wings with cut off wingtips and vertical tail surfaces of increased size (to provide more stability at higher speeds).

Defined by the unconventional shape of the Astazou, the first 1110 was an even odder looking machine than the original 1101. However, with almost double the power of the piston models – and aerodynamic refinements that removed the high-speed effects first experienced by the second Bf.108C-1 – the 1110 easily took the title of the fastest Nord single prop in the sky (photo source: 1000aircraftphotos.com)

Like the Me-208 though, only one of these amazing aircraft would actually survive to fly another day once the Astazou test program came to an end. Owned and operated by the Association Antilope under the reg F-AZNR, the above pictured example is still airworthy and beautifully maintained, happily plying the airshow circuit in France on a regular basis πŸ™‚ .

A beautiful atmospheric shot of F-AZNR by Mr. Eric Hannequin (photo source: Mr. Hannequin’s Flick gallery)

The wind that keeps on blowing

While the type’s prime – in any version – had passed a long time ago, its status as one of the preeminent touring aircraft of the 30s had naturally had an effect on its current status of a desirable WW 2-era warbird πŸ™‚ . Most estimates suggest that somewhere between 25 and 30 Taifuns and Nords are still airworthy today – a number of which are, unsurprisingly, operated in Germany. Aside from Messerschmitt’s own historic flight – the previously mentioned Messerschmitt Stiftung, part of the EADS consortium – another famous 108 operator is Lufthansa’s vintage aircraft division, the Lufthansa Stiftung. Possibly the best known of all surviving 108s, the company’s silver B-1 – registered D-EBEI – also shows that there’s still some mischevous spirit left in one of the world’s most serious companies; for a Taifun named Elly Beinhorn was just too good an opportunity to pass up πŸ˜€ .

Looking resplendent in a period scheme. Like several surviving examples – some of which still tend to clock up decent flying time – D-EBEI was refitted with a modern propeller and constant speed unit, to avoid wearing out the nowadays hard-to-come-by Me P7 (photo source: D-OTTI gallery at arcor.de)

D-EBEI gallery @ Airliners.net

For photos of other flying – and museum – examples, some of which are too good to cram in here, you can visit these galleries at Airliners.net, which I’d sorted by type πŸ™‚ :

Bf.108 Specifications & Performance

A table view of the specs of the Bf.108B-1, B-2 and D-1 (Pingouin numbers were broadly similar). Click the image to go to the bigger version (source: http://www.network54.com/forum; or simply click on the Aeronet Aviacion Part 1 link)

Version overview

Since keeping track of all the 108 versions can be a handful – and was quite a frustration for me as I was writing (and rewriting) this πŸ™‚ – I’ve decided it would be prudent to sum them all up in one place, along with a few of their distinguishing features:

M.37 the first prototypes, used for initial flight testing and equipped with roll spoilers
Bf.108 the designation adopted during acceptance tests, identical to the M.37
Bf.108A 1934 competition version, modified with short-span ailerons
Bf.108B-0 pre-production series, each aircraft incorporating slightly different features
Bf.108B-1 the first production version with folding wings, Argus Ar 10C engine and fixed-pitch prop (Me P7 variable-pitch as an option)
Bf.108B-2 B-1 with folding wings removed and the P7 fitted as standard
Bf.108C-1 initially a Siemens radial version; later reused on the proposed HM502 V12 high-speed model
Bf.108D-1 final German production version fitted with a constant-speed prop, Ar 10R engine, more powerful electrics, improved fuel system and a modified vertical stabilizer; produced mostly in France
Nord 1000 Pingouin post-liberation Bf.108B-2s, incorporating the B-1’s folding wings and the D-1s vertical stabilizer
Nord 1001 Pingouin I new-build 1000s fitted with the 233 HP Renault 6Q-11 engine
Nord 1002 Pingouin II new-build 1000s fitted with the 240 HP Renault 6Q-10 engine
Me-208 two prototypes of the Bf.108B-2 modified with tricycle gear, designed in France
Nord 1100 Noralpha the post-war designation of the only Me-208 prototype to survive the occupation of France
Nord 1101 Noralpha I / Nord Ramier production-standard 1100s fitted with the 6Q-10 engine
Nord 1102 Noralpha II proposed 6Q-11 model, never built
Nord 1104 1101 modified with the Potez 6Dba engine, one built
SFERMA-Nord 1110 Noralpha-Astazou two 1101s modified as testbeds for the early Turbomeca Astazou tubroprop

Sources

Rare Aircraft – Messerschmitt Bf.108

By me

TEMPORARY NOTICE: I’ve noticed today (16 September ’10) that EADS have apparently redesigned their Company History webpages and removed some of the photos I’ve linked to in this post (which now show up blank). I will try to and dig up where have they been moved to, but it may take awhile…

NOTICE NO.2: Due to my two-year-long failure to finally address the above (it really did take awhile as it turns out πŸ˜€ ) – and the new friendlier visual format of this blog – I’ve decided to outright rewrite and refresh the entire post, adding a bit of new information and photos, and correcting the odd mistake. This new & improved version – posted as of 21 September ’12 – can be seen here :).

When the first Bf.109s faced their German rivals in mock dogfights in the mid-30s, few observers – in any country – were left in any doubt about the potential of Messerschmitt’s first complete fighter design. International flying competitions in the years preceding WW2 had further underlined these impressions, while an all-up production run of almost 35,000 examples, spanning more than a decade in one form or another, and an impressive – though in the later stages of the war a bit diluted – combat record removed any doubt remaining.

A very advanced design by contemporary standards, the Bf.109 was not really ground-breaking per se; when all was said and done, it had not really introduced anything completely new into the rapidly advancing world of interwar aviation. What it had done however was combine all the cutting-edge technologies of the time into one airframe – the monoplane configuration with high wing loading; the powerful liquid-cooled V engine and its variable-pitch prop; retractable gear; the enclosed cockpit…

Two more of its immediately apparent trademark features were the automatic leading edge slats and – for a combat aircraft – very low weight, courtesy of a clever design philosophy that made the aircraft simple and cheap to build and quick & easy to service and maintain – not to mention making it tough, durable and reliable out in the real world. And while the big engines and retractable gear could easily be traced to some of the eminent combat aircraft of the time, these two were inherited from a far more unfighterish source – the Bf.108 tourer…

The Messerschmitt Stiftung’s beautiful Bf.108B-1 in some accurate historical colors (photo from: commons.wikimedia.org)

1. When I grow up I want to be a fighter!

The aircraft that would (among other things) lend most of its technical solutions and complete tail unit to the early Bf.109 started out in life as the four-seat* M.37 tourer of 1934. Designed by the young Willy Messerschmitt, Bayerische Flugzeugwerke‘s chief designer, the M.37 was intended to compete in the 4th Challenge de Tourisme Internationale being held that same year. This interesting general aviation competition – wish they held something like this today! – included categories such as “Short Takeoff”, “Short Landing”, “Fuel Consumption”, “Minimum Speed”, “Maximum Speed” and “Technical Trial”, as well as a 9500 km race across Europe and Northern Africa (that had also stopped in Zagreb! :D).

*though intended as a four-seater, the M.37s and the early 108s were operated as two-seaters, with the rear seats permanently removed to provide some storage space (with virtually all pre-Bf.108B versions having been used for races and flying competitions), giving the impression that they were outright designed for just two

Based partly on Messerschmitt’s previous M.29 – designed in a similar vein for the 1933 competition, but never taking part due to a spate of crashes – and the M.35 aerobatic trainer prototype, the M.37 was a sleek low-wing stressed-skin all metal monoplane with retractable gear, an enclosed cockpit, full-length flaps with roll control provided by roll spoilers (!) and a variable-pitch prop – just enough to make it that less inconspicuous among the wood and fabric biplane crowd :). The unorthodoxy continued under the skin as well: the wing was made around only one spar, a design that was made to work by Messerschmitt’s extensive glider building experience gained in the Versailles Treaty-limited post-WW1 period. The famous mechanical leading edge slats could be manually extended to greatly improve the airflow over the outer wing sections – which were likely to stall first – reducing the stall speed to just 61 km/h (33 kt). This in turn significantly shortened the take-off and landing rolls – not quite to STOL levels, but very close – and increased low-speed maneuverability and handling at high angles of attack.

The leading edge slats on the Bf.109. Interestingly though, these were a British innovation, patented by Handley-Page several years before. To be able to use them, Messerschmitt had traded the build rights to his own patented design, the aforementioned single-spar wing (photo from: German Bundesarchiv via Wikipedia)

As with the wing, the whole design philosophy was to make the aircraft as simple as possible, with the fewest realistic number of parts used to create a light and durable airframe. Functional minimalism. And it had worked – compared to other (later) metal aircraft of similar design, the M.37 was indeed among the lightest and best performing. Official flight testing prior to the competition was marked by the general enthusiasm of all the pilots that had flown it, prompting the German aviation ministry – the Reichsluftfahrtministerium, RLM – to give the aircraft a tentative green light as the Bf.108. Of note here is the oft-confused designation: “Bf” obviously stood for the initials of Bayerische Flugzeugwerke; however, when the company was renamed into Messerschmitt Flugzeugwerke in 1938, all subsequent designs were given the “Me” prefix. The designs that had been produced prior to the name change kept their old prefixes – so there never really was an “Me-108” as can be found in some Internet sources.

However, despite all its qualities, one aspect of the aircraft raised doubts among some test pilots – the roll spoilers. With the full length of the trailing edge taken up by the flaps – increasing the wing area by a whopping 8% when extended – there was no space for any ailerons; roll control was then provided by spoilers on each wing that would create a difference in lift between the wings. For example, if you had wanted to turn left, the roll spoiler on the left wing would extend, disrupting the airflow over it and reducing lift. The right wing would now be producing more lift and sort of tip the aircraft around its center of gravity, causing the aircraft to roll to the left. This was fine in theory – and is used on a number of civil and military aircraft today – but back then it was eyed with suspicion and more than its fair share of antagonism. This came to a head when test pilot von Dungern was killed in a 108 while testing the spoilers, presumably somewhere near the edge of the envelope.

With the RLM’s well documented dislike of Messerschmitt threatening to ground the 108 – like it had the M.29 a year before – there was no other option but to revert to a conventional aileron arrangement. “Conventional” should be taken with a grain of salt though, because the resulting arrangement still managed to raise an equal number of eyebrows…

You can see that Messerschmitt was adamant with his high-lift devices: shortening the flaps a bit, he managed to just squeeze in two small 30-cm wide ailerons, lengthened to make up for their lack of span :). Note also the upper tailplane bracing that would be removed on later versions. The aircraft pictured was one of the four intended for the race – and one of three actually competing – and is to that end coded “11” (photo from: http://www.network54.com/forum)

In this form the aircraft became known as the Bf.108A, the designation under which it would be entered in the competition. It’s beautiful handling and avantgarde features did not help its case there though, when the far lighter, nimbler and simpler wooden aircraft wiped the floor with it for most of the competition…

Yet, the Bf.108A did notch up several wins, all of which would steer its later development into the tourer we know today. The top three aircraft in the “Fuel Consumption” category for example were all 108s – with the winner notching up an impressive 10 kg (14 l)/100 km. This number, in many cases exceeded by today’s SUVs, was made even more impressive by the fact that the 108A was not powered by some microscopic fuel-sipping engine, but a 220 HP Hirth HM 8U inverted V8 (how’s that for a GA engine? :D). This had also helped in the “Maximum Speed” event, where the 108s again took the first three places, with the slowest – at 283 km/h – being 30 km/h faster than the next contender. The trans-Europe race was less of a success, with one 108A, flown by Theo Osterkamp, placing fifth – but the result was due more to external influences (weather and navigation) and the scoring system (points being based on the total average cruise speed, including stationary periods, which meant a weather delay for example would cause a decrease in the average) than the aircraft itself. Indeed, when everything fell into place, the 108s had regularly posted the highest flying average speeds – including the leg to and from Zagreb :).

In total, when the competition tally was done, the three 108s were ranked 5th, 6th and 10th (out of 19). But more importantly, their demonstrated low fuel consumption, high speed and beautiful handlingΒ  – and comfy leather seats! – had lent them well to cross-country touring. A clean, aerodynamic airframe able to go fast on not much power – sounds very much like the Lancairs, Cirruses and Diamonds of today, doesn’t it? πŸ™‚

Another quarter view of “11”. The early pre-series production 108s were the only members of the family to sport VDM three-bladed props (photo from: http://www.eads.net)

This did not slip past the then cash-strapped BFW, where Messerschmitt had decided to capitalize on the type’s success by adapting it for series production. To this end, a batch of pre-production Bf.108B-0 models was made (though they were still commonly known as the Bf.108A) with each successive aircraft representing a slight move toward the production standard.

In 1935, these had also started making a name for themselves – quite literally. The fastest light tourer in the sky, it was chosen by famous German aviatrix Elly Beinhorn for her record-breaking flight from Berlin to Constantinopole (now Istanbul, Turkey) and back. Her little 108B-0 had more than lived up to its Taifun nickname, taking just 13 and a half hours to cover the 3,470 km trip, flying along at a respectable average groundspeed of 257 km/h (139 knots).

Ms. Beinhorn and “Taifun” posing after their long flight. Easily seen here is the A/B-0 model’s “bathtub” cowling for the Hirth engine (photo from: http://www.luftarchiv.de)
The simple gloss white paint scheme worn by “Taifun” for its record flight (picture from: http://www.aviation-ancienne.fr)

Success like this had opened the floodgates and the 108’s already considerable popularity skyrocketed (as much as it could have in the general aviation scene of the 30s). The full potential of the design had immediately become obvious at the BFW works, where Messerschmitt set about turning the 108B-0 into the definite four-seater, a true cross-country airplane. The result was the Bf.108B-1, now adopting Taifun as its official name :).

Ms. Beinhorn posing in a production Bf.108B-1, sporting the type’s distinctive “Messerschmitt Taifun” logo (photo from: http://www.ctie.monash.edu.au)

The idea behind this version was to make the aircraft more production- and consumer-friendly, so first to go was the A model’s powerplant. The expensive and hard-to-come-by VDM variable pitch propeller was replaced with a simpler and cheaper two-blade fixed pitch prop (though an Me P7 two-blade variable-pitch unit was offered as an option), while the HM 8U engine was swapped for the readily available 240 HP Argus Ar 10C inverted V8. The wing too was made a bit duller by the reversion to a fully conventional aileron/flap arrangement – though it had also gained a wing folding mechanism (at the root) for easier transport by road or rail. The slats were now made automatic, extending at a certain speed by air pressure. Additional minor changes included the removal of the upper tailplane bracing mentioned previously, the replacement of the next-to-useless tailskid with a tailwheel, and the shortening of the glazed canopy over the rear seats.

In this role and form, the 108B-1 had continued to participate in international competitions, rallies and fairs – most notably the 1936 Olympic Games held in Berlin – but this time under the increasingly ominous banner of Nazi propaganda. Indeed, even before WW2, the fast-growing Luftwaffe had been eying the 108 as a liaison and communications aircraft to replace the obsolete and lumbering biplanes then being used.

A later Bf.108B-2 in a pre-war civil scheme, showing off some of the changes from the A model. Note the shallower and more oval cowling, the less-extensively glazed canopy and the tall tailwheel (photo from: http://www.network54.com/forum)

However, the 108’s biggest contribution to the Wermarcht’s war effort was as the basis – the parts donor if you will – for the amazing Bf.109. In a fascinating display of lateral thinking, in 1934 Messerschmitt simply took the plans for the 108A and modified them into a single-seater with a narrower fuselage, a big V12 up front – a Rolls-Royce Kestrel for the first prototype, proving that irony was alive and well back then – and some boom booms in the slightly modified wings. Apart from the changes needed to fit all of these together, the rest was all 108 :).

The fourth prototype of the Bf.109, the Bf.109V4 (which served as the model for the first production B series). When you remove the deeper and narrower fuselage, you can see many elements of the 108’s design – including the tail unit. Even the pilot’s seat was in the same place as the rear seats on the 108 (photo from: http://www.tgplanes.com)
A production Bf.109B of the Legion Condor during the Spanish Civil War. The early versions’ radiator was – as is visible here – mounted below the nose as opposed under the wings in E and later models, giving this version a clearer Bf.108 lineage (photo from: http://www.hrvatski-vojnik.hr)

While the wildly differing roles of these two aircraft may have raised some doubts, the 108’s base design turned out to be just the thing for the new fighter. It’s simple construction meant the 109 was light and maneuverable – and we all know how that turned out in the early stages of the war – and it’s relatively low parts count meant it was simple to maintain and repair out in the field with facilities and tools at hand. Lacking complicated whizz-bang construction elements meant it was far more tolerant of combat damage and the chances of a disastrous “lucky” shot disabling the entire aircraft were greatly reduced. At the same time, the clean airframe did not want for performance, so the 109 could do with less power than a similar aircraft – quite a welcome feature given its notoriously short range.

2. Oh, the irony!

Having had the (mis)fortune of being the most advanced light aircraft in the world during a period of turbulent political changes, the 108B-1 had quickly accumulated its fair share of odd operators. Apart from the “usual” ones such as Bulgaria, China and Japan, there were a couple of… unexpected ones to say the least, including the Royal Yugoslav Air Force. The dozen or so examples bought in 1939 were part of a larger batch that had also included approximately 60 Bf.109Es and quantities of spare parts – all paid for not with actual money, but in strategic materials such as iron, aluminium, copper and coal, materials abundant in the lands of former Yugoslavia, but scarce and badly needed for the war buildup in Germany. While the 108s were to lead relatively uneventful lives in the training and communications roles, the 109s would enter the history books during the German invasion of 1941 as the only time Bf.109s would ever face Bf.109s in outright aerial combat :).

Ε -08 (“Ε ” for “Ε‘kolski”, literally meaning “schooling type”) at a field that could even be Borongaj πŸ™‚ (photo from: http://www.network54.com/forum)
Yugoslav 108s were well known for their interesting paint schemes, with camouflage ones like the above behing the most prevalent (picture from: http://www.network54.com/forum)

Next on the scale of improbable is the – the US military :D. While it wasn’t uncommon for the USAAF to fly and test captured Axis aircraft, the single Bf.108B-1 – bought by the US Military attachΓ© to Berlin in 1939 – had never left Germany and was used as a high-speed staff transport. Designated the XC-44, this aircraft was flown all the way until 1941 when it was repossessed by the German government following the US’ formal declaration of war on the Axis powers following Pearl Harbor.

Quite possibly one the rarest paint job ever to be applied to a Messerschmitt πŸ™‚ (picture from: http://www.network54.com/forum)

But by far the most interesting 108s were the Messerschmitt Aldons, the designation of four examples impounded by the RAF at the beginning of WW2. Used in the communications role, the 108 had proved to be the fastest type for that purpose in the UK, though its close semblance to the Bf.109 was to cause some worrying “identification problems” among defending RAF fighters…

(and for those of you who think “How can the 108 possibly be mistaken for a 109?”: the first of the long-nose RR Griffon-engined Spitfires – the Mk XIIs – were delivered with clipped wingtips, intended to improve roll rate and increase speed at low altitudes, a feature well known and seen on a number of previous marks. On the ground, the Spitfire’s famous elliptic wing planform was still more than obvious in spite of the change. Up in the air however, on their first few sorties, only their new-found speed advantage kept them from being shot out of the sky by patrolling Hawker Typhoons which had mistaken them for attacking 109s… and these are Spitfires, well removed – on the ground – in shape, form and color from any version of the 109).

One of the four Aldons painted in standard RAF camo colors (photo from: Wikipedia)
I must say, the 108 looks quite handsome in this scheme :). But despite the big RAF roundel, they were sometimes mistaken for 109s in the confusion or air combat (picture from: http://www.network54.com/forum)
Another catchy scheme, which again didn’t help in matters of identification… (picture from: http://www.network54.com/forum)

The post-war period too saw its share of odd 108 operators, including Czechoslovakia (where the type was known as the K-70), Poland and the Soviet Union, all of which had flown a few aircraft captured during the final days of WW2. For the full photo history of the 108’s civilian and military service around the world, you can visit these two excellent pages, a goldmine from which I’ve linked many of the above photos:

3. Western promises:

Unlike its armed cousin, the 108 did not go through new versions like pairs of socks. Apart from the Bs, there was only one other major production version; and aside from that there were curiously few experimental models as well. But what they lacked in quantity they had certainly made up in quality…

By far and away the most normal of these was the C-1, an ungainly looking 1936 modification that had seen the standard B airframe fitted with a Siemens Sh 14A-4 7 cylinder radial, churning out just 160 HP. Combined with the radial’s large cross-section – which necessitates more power to overcome drag – and 80 HP (33%!) less power than the Argus engine, you can imagine why this was a one-of model…

Used solely for propaganda purposes during the 1936 Olympic Games, the C-1 had managed to clock up 21.600 km without incident, shuttling film rolls of the games between Berlin and Stockholm. Abysmally underpowered,Β  it was later re-engined back to the standard Argus V8 (photo from: http://www.network54.com/forum)

At the other end of the spectrum was a never-built version that some sources also label as a C-1 (it could entirely be possible that the designation was re-used). Diametrically opposed to the Siemens model, this C-1 was to have been a high-speed version, fitted with a Hirth HM 512 inverted V12 that would have developed a whopping 400 HP on takeoff! πŸ™‚ Ground testing in 1938 had shown that the airframe started experiencing noticeable vibration above 325 km/h, which progressively became so severe that it had threatened to tear the airframe apart. Given the scope of engineering changes that would have been necessary to make this work, the project was quietly dropped…

That the only way was up – literally – was demonstrated in 1939 by a specially modified high-altitude 108B-1, built to capture the altitude record for its class. Fitted with a turbocharged Hirth HM 508 inverted V8 producing 270 HP (and also providing bleed to a pressurized cabin), it had reached an impressive 9,125 m (29,930 ft) of altitude in the hands of Hirth’s boss, Hermann Illg.

The series production models were less exciting however – and were suffering from an acute case of Cessna Skyhawk-itis as well :D. If you took 10 random Skyhawks of the same model and same production year and lined them up, I guarantee that you’d be able to find at least one unique feature or option on each of them… a double landing light here, the static port moved to there, an instrument layout just that little bit tweaked… The Bf.108 was no different, with options from one version sometimes being used on another, which made sorting them by model numbers a bit difficult – but after roving the Internet far and wide I think I managed to nail it (at least in general terms):

  • B-1 – the already described base model
  • B-2 – generally similar, but with the wing fold system removed and the variable pitch Me P7 prop fitted as standard. These versions could easily be recognized by the thinner metal prop blades connecting within the spinner hub
  • D-1 – produced from 1941, this was the first model intended outright for military use and featured a modified vertical stabilizer, improved fuel feed system, a more powerful electric system, vertical speed indicator, windscreen wiper and a constant speed propeller (whose crowned spinner became the model’s distinctive outside feature) being turned by an As 10R engine of the same output as the C model. It should be noted here that “variable pitch” and “constant speed” propellers are not quite the same thing: a constant speed propeller will automatically regulate the pitch of the propeller blades to maintain the same RPM regardless of throttle setting. The variable pitch system however will only change the pitch to a preset setting (sort of like shifting up a gear in a car), with the RPM still regulated by the throttle
A beautiful lineup of what I believe are B-1s. The source of the photo, http://www.eads.net, says these are D-1s, but the fixed pitch props (note how the props are single piece and go around the spinner) raise some doubts…
Despite the Bf.108 not being the best-looking tourer the world has ever seen, it does have an elegant and purposeful appearance (photo from: http://www.eads.net)
A Bf.108B-2 (by the looks of the prop) inflight. Though not as fast as today’s high-end piston singles, the 108 has much more class :). You’d attract far more looks with this than with any Cirrus… (photo from: http://www.eads.net)
The only photo of the original D-1 I could find… (photo from: http://www.preservedaxisaircraft.com, taken by: Alexander Hurrle)
For visual recognition: the same type of spinner as on the D-1 as seen on a Pilatus P2 (photo from: http://www.pilatus-p2.de)

The D-1 would also be the last Bf.108 version produced in Germany before production was transferred to France at the beginning of 1942. In a bid to free up domestic production capacity for badly needed Bf.109s, the Bf.108B-2 and D-1 were allotted to the SociΓ©tΓ© Nationale de Constructions AΓ©ronautique du Nord, SNCAN, just outside Paris, where they would remain till the end of the war – with interesting consequences.

Following the liberation of France, SNCAN – having produced just 170 aircraft in two years, out of the original type’s total run of about 880 – was left with a significant number of uncompleted airframes and engines. Deciding it’d be a waste to throw them all away – and desperate to gain a foothold in the country’s recovering economy – the top brass at SNCAN had decided to restart production of the aircraft, but this time as the Nord Pingouin (what an insult – demoted from a typhoon to a cute polar animal :D). The base model, the Nord 1000, was virtually identical to the Bf.108B-2, using the same German engines and systems up till now standing around in the company’s warehouses.

Apart from French colors, there was very little to distinguish the 1000 from the Bf.108B-2 – except for the provision of the B-1’s wing fold mechanism (picture from: http://www.network54.com/forum)

Once these were exhausted, it was a relatively simple matter to remanufacture the aircraft from the original plans, the production tooling being already set up and waiting. However, the engines had proved to be a bigger problem, having been imported from Germany (where the Argus factory was leveled in the mean time). To get around this, SNCAN had decided for the easiest method – using a locally built engine of similar power. The only one available was the 233 HP Renault 6Q-11 6 cylinder inverted inline, giving the new Nord 1001 Pingouin I a significantly pointier nose than the Bf.108’s. A generally similar Nord 1002 Pingouin II – the most common variant – differed only in having a slightly more powerful (and right-turning) 240 HP 6Q-10 engine, bringing the power rating up to Bf.108 levels (not that the 7 HP mattered much). In total, 286 Pingouins were produced, bringing the overall 108 total to above 1,100 examples (unfortunately I could not find the year French production ended – but with the aircraft remaining in service till the early 60s, and their low production volume, I’d wager a guess that 1950 or thereabouts could be the year).

A Nord 1002 in early Bf.109A colors. Note the deeper and longer nose for the taller (but narrower) 6Q engine (photo from: http://www.airventure.de)

Nord 1002 @ Airliners.net (photo 1)

Nord 1002 @ Airliners.net (photo 2)

Nord 1002 @ Airliners.net (photo 3)

Note: some of the surviving aircraft had later been retrofitted with “normal” Lycoming and Continental piston engines and have a shorter, broader and more oval cowling. For the sake of simplicity, I decided to represent only the original Renault engine models here…

4. A (third) leg to stand on:

In the meantime, back during 1943, SNCAN – under guidance from Messerschmitt – was working on modifying the Bf.108B-2 with tricycle gear, which was coming into vogue at the time. The two prototypes converted as such were designated the Me-208 – in line with the designation issue mentioned previously – but only one had survived the war intact, to be renamed the Nord 1100 Noralpha. Like with the base 108, SNCAN had decided to finish the design and market it – having already done 90% of the work – with the result being the Renault 6Q-10-engined Nord 1101 (known as the Ramier in French Air Force service) whose production ran to the 205 example mark.

One of the surviving Noralphas during a tipsy landing. Though very similar to the Me-208, the Noralpha was already starting to significantly depart visually from the Bf.108 (photo from: http://www.flugzezginfo.com, taken by Mr. Karsten Palt)

Nord 1101 Noralpha engine shot @ Airliners.net

Like the 108, the Noralpha had a knack for testing out different engines :). Along with the planned, but never built, Renault 6Q-11-engined 1102 Noralpha II, the 1104 was a one-of model equipped with a Spanish Potez 6Dba engine of identical 6 cyl configuration and the same 240 HP as the 6Q-10.

But the ultimate expression of power – indeed of the entire 108 design – were the two 1959 Nord 1110s, re-engined with not a puny piston, but a 550 HP Turbomeca Astazou II turboshaft (lifted from a helicopter)! One of the two, registered F-AZNR, is still alive and flying today :).

A beautiful atmospheric shot of the sole surviving 1110 by Mr. Eric Hennequin (photo from: Mr. Hennequin’s Flickr gallery, click on the photo for the link)

F-AZNR @ Airliners.net (photo 1)

F-AZNR @ Airliners.net (photo 2)

5. Penguins and Typhoons live longer:

Today, it is estimated that there are 25-30 flying Bf.108s remaining worldwide (though I’m not sure whether that includes the Nords as well), a number being operated – naturally – in Germany, and by no less than Lufthansa’s and Messerschmitt’s “history flights” (the Deutsche Lufthansa Berlin Stiftung, www.dlbs.de, and Messerschmitt Stiftung respectively). Lufthansa’s example, D-EBEI – quite possibly the most famous 108 today – also proves that there is some humor left in today’s straight-face corporate world: for irony doesn’t quite cover a Bf.108 Taifun named Elly Beinhorn… πŸ˜€

D-EBEI @ Airliners.net (photo 1)

D-EBEI @ Airliners.net (photo 2)

While virtually all survivors were retrofitted with modern constant-speed prop units, one great-looking B-1 model, D-EBFW, is still proudly sporting its fixed pitch prop :).

D-EBFW @ Airliners.net (photo 1)

D-EBFW @ Airliners.net (photo 2)

For more modern photos – there are some beautiful ones and it wouldn’t make sense to cram them all in here – you can visit these Airliners.net “galleries” I’ve linked below, sorted by type:

6. Bf.108 Specifications:

A table view of the specs for various production Bf.108s (B-1, B-2 and D-1). Click the image to for the bigger version. Pingouin numbers were broadly similar (taken from: http://www.network54.com/forum – or simply click on the Aeronet Aviacion Part 1 link)

7. Version overview:

Reading through this prior to posting it, I’ve decided it’d be a prudent move to sum up all the Bf.108/Nord versions in one place, as trying to keep track of all of them was giving me a headache :). This is only a quick list with some distinguishing features, for reference:

  • M.37 – the first prototypes, used for initial flight testing, equipped with roll spoilers
  • Bf.108 – the designation adopted during tests, structural identical to the M.37
  • Bf.108A – 1934 competition aircraft modified with ailerons
  • Bf.108B-0 – pre-production versions
  • Bf.108B-1 – the first production version, with folding wings, Argus Ar 10C and fixed pitch prop
  • Bf.108B-2 – B-1 with the folding wings removed and the Me P7 variable-pitch prop fitted as standard
  • Bf.108C-1 – the Siemens radial model and/or the proposed HM 502 V12 model
  • Bf.108D-1 – final German production version fitted with a constant-speed prop, As 10R engine, more powerful electrics and miscellaneous small changes, produced mostly in France
  • Me-208 – two prototypes of the Bf.108B-2 modified with tricycle gear
  • Nord 1000 Pingouin – post-liberation Bf.108B-2s produced by SNCAN from existing fuselages and Argus engines
  • Nord 1001 Pingouin I – 1000s fitted with the Renault 6Q-11 233 HP engine
  • Nord 1002 Pingouin II – 1000s fitted with the 240 HP, right-turning 6Q-10 engine
  • Nord 1100 Noralpha – the surviving Me-208 prototype
  • Nord 1101 Noralpha I/Ramier – production-standard 1100s fitted with the 6Q-10 engine
  • Nord 1102 Noralpha II – 6Q-11 engine model, never built
  • Nord 1104 Noralpha – Potez 6Dba testbed
  • Nord 1110 – two 1101s re-engined with 550 HP Turbomeca Astazou II turboprop engines

Sources: