Start yer engines!

[apophenia]

Immediately after WW2, 'Texan Class' air racing took off throughout the Western World. Initially, in the 'Unlimited Texan Class', racers could be as highly modified as desired. The sole constraint was that racers had to be based on Texan, Harvard, Yale, or Wirraway airframes.

One racer that tested the boundaries of 'Unlimited Texan Class' racing was the 'Ballarat Boomer'. This was a modified Commonwealth CA-14 Boomerang fighter. But, since the Boomerang was derived from the CAC Wirraway trainer, the owners of the 'Ballarat Boomer' argued that their aircraft met Class restrictions.

Dubbed a 'CA-14R' (for 'Race'), the 'Ballarat Boomer' was a de-militarized Boomerang fitted with a race-tuned Twin Wasp engine, a one-piece windscreen, and the wingtips were replaced with scalloped fairings. The 'Ballarat Boomer' flew well but, unfortunately, 'Unlimited Texan Class' rules had firmed up [1] and this aircraft was disqualified from racing.

The 'CA-14R' was fitted with standard Boomerang wings and was operated as an airborne billboard. All was not lost. Perth Aero Engineering plc had begun work on an 'Unlimited Texan Class' racer. This aircraft was a hybrid of Australian CA-10 Wirraway and North American AT-6A Texan components. The short-span 'CA-14R' wings were bought for installation on this racer.

The 'Pride of Perth' had a number of other radical features. A new cockpit was created between the original two seats in Wirraway centre fuselage (which was joined to a Texan rear fuselage and its tailplane). The cowl-line was slightly lowered and the new cockpit covered with a low-profile canopy. Other features were a modified Boomerang spinner and a retractable tailwheel taken from a North American Mustang.

Registered VH-POP, the 'Pride of Perth' had an enviable race record in its first year of operation. Alas, its success was short-lived. The combination of short wings and a highly-strung racing engine proved to be the undoing of the 'Pride of Perth'. An engine failure on approach to Fremantle, WA, resulted in a hard landing and ground-loop that VH-POP never recovered from.

________________________

[1] The flexibility of 'Unlimited Texan Class' rules had been tested in the US when a modified North American P-64 fighter was entered. As with the 'Ballarat Boomer', the P-64 owners had argued that their machine was a Texan derivative and therefore qualified to race. However, officials concluded that the smaller fighter airframe gave an unfair advantage over race-modified Texan airframes.
________________________

[Acree]

I like these a lot, but I wonder if using the original-position rear cockpit on Pride of Perth would not have been both easier (structurally) and more effective (aerodynamically).  Plus it would have looked really cool with a rear positioned canopy, though landing and taxiing would have been problematic.

Really nice work, though! 

[Tophe]

  Delicious hybrid!

[GTX_Admin]

 :)

[apophenia]

Thanks folks. Acree: A rear-placed cockpit was my original plan ... and it certainly would have been simpler, structurally. But the aesthetics of the central canopy appealed to me.

BTW: On the digital drawing board is another racer with even worse visibility than a rear-cockpit Harvard 

[AXOR]

Nice ones  :)...Every time it's a pleasure to see your work !
Today I saw many of your old stuff,maaan you made some great racers over the years.I wonder what you will invent for this GB...

[Brian da Basher]

I just love the idea of a Boomerang racer which delights me to no end!

Brian da Basher

[apophenia]

Thanks folks!

Another US air racing series based around the T-6 Texan was the 1500C or 1,500-mile circuit. In 1500C rules, engine power was restricted to the 600 hp of the Pratt & Whitney Wasp and no external fuel tanks were permitted. Another constraint was the enforced use of unmodified T-6 outer wing panels and tailplanes. The goal of these restrictions was to encourage wins by superior airmanship while flying near-stock Texan aircraft.

Race pilots, however, are always looking for an edge. As an example, little about Texas Trouble looks like a standard Texan. Amarillo Aviation 'detailed' the T-6G airframe, smoothing every rivet and other fasteners. In common with many 1500C racers, the front cockpit was replaced by a large fuel tank. The rear cockpit was then covered with a carefully-faired, one-piece bubble canopy. [1] But the most radical changes were reserved for the powerplant.

Unable to increase Texas Trouble's engine power, Amarillo Aviation focused on drag-reduction. The Wasp was first given fan-cooling which allowed a large-diameter propeller spinner and a more streamlined cowling. Then, a custom exhaust system (of individual exhaust pipes) was developed in hopes of augmented thrust. To re-establish the centre-of-gravity, the powerplant was also moved aft on shorter engine-bearers.

(Top) Amarillo Aviation's highly-modified T-6G, Texas Trouble (NX01784A), as first rolled out.

Rules are meant to be bent ... and few went further than the Grumman employees' group who developed the Bethpage Bullet. The 'Bullet began as F4F fuselage components donated by Grumman to its hobbyist workers. True to 1500C rules, the F4F received a single-row P&W Wasp engine. Then the Wildcat fuselage was modified to accept the required tailplane and outer wing panels from an AT-6 Texan. The rules were being followed ... just not as intended by the drafters of the 1500C regulations!
 
To streamline the new racer, the first order of business was to 'shave' the Wildcat's top deck. Much of the fuselage spine and the canopy itself was removed. A flush canopy was fitted over a new, rear-positioned cockpit. [2] In flight, pilot visibility was provided by a periscope. On take-off and landing,  the Bethpage Bullet's visibility was even worse. (The pilot had to tip his canopy up to form a windscreen and slide his periscope aft to poke his head out of the opening).

Further streamlining was intended with the use of an immense propeller spinner through which cooling air was fan-driven over the Wasp engine. The concept was better than the reality -- where constant engine overheating was the cost. After brief testing, this arrangement would be dropped in favour of a standard Texan cowling (albeit with a large spinner on the prop hub). Re-cowled, the 'Bullet became one of the fastest 1500C entrants but was eventually lost in a landing accident. Not too surprising considering the Bethpage Bullet's combination of narrow-track Wildcat undercarriage, 'running board' T-6 outer wing panels, and minimal pilot visibility.

(Bottom) The Bethpage Bullet (NX8029) with original (scrap view) and final cowling arrangements.

[CiTrus90]

Really like the extreme Bethpage Bullet :)

[apophenia]

The 'Ranger Races' were highly popular events in the US. For racers, the lucrative Fairchild Cup was one incentive. Another was ease of entry. Any airframe was acceptable so long as it was powered by the comparatively modest Ranger air-cooled V-12 powerplant.

The European equivalent to Ranger Racers was what became the Delta Unlimited. Initially, any lightweight, air-cooled engine of European manufacture was acceptable. In Britain, Supermarine quickly knocked together a 'featherweight' version of the pre-war High-Speed Spitfire. However, the development was much slower for its powerplant - the de Havilland Emperor Gipsy (a V-16 derivative of the Gipsy 12).

The 'Emperor Spitfire' was quick but the reversed-flow cooled Emperor Gipsy was a disaster. Continuously overheating, the DH engine's long crankshaft was also prone to failure. After scrubbing in its first four races, and suffering an inflight engine fire durings its fifth, the Emperor Spitfire was withdrawn. It would later reappear as the High-Speed Spitfire Racer -- re-engined with a V-12 Isotta Fraschini Delta and sporty a jaunty livery of British Racing Green with gold-coloured trim.

In France, an association of Armée de l'Air officers assembled a racer from components from a number of scrapped Dewoitine D.520 fighters. At first glance, 'Pare a viver!' appeared to be a simple re-engining of the D.520. It was anything but. The entire upper fuselage had been shaved to lower its profile. The new and highly-streamlined canopy covered an aft-placed canopy.

Less obviously, the forward decking was removable to accomodate a second cockpit (to allow entry into 2-seater 'tourer' class races). The undercarriage also received attention -- smaller-diameter main gear wheels replaced the originals and a retractable tailwheel (from a junked Luftwaffe Bf 109F) fitted.

[AXOR]

Good story,great profiles !

[jcf]

 :)

Don't forget Harry Miller. 

http://beyondthesprues.com/Forum/index.php?topic=3909.0

[elmayerle]

Beautiful concept!  So, will a racing version of the Re.2001Delta be showing up?

[Brian da Basher]

More great stuff! They're all real lookers but I especially like that Dewoitine!

Brian da Basher

[Tophe]

Good profiles!
The operator that painted the French name made a little mistake, no problem. "Pare à virer" means nothing, the right words are "Paré à virer" (ready to turn), maybe the painter made a mistake for bigger smiles...

[GTX_Admin]

 :)

[apophenia]

Cheers folks. Tophe: Thanks ... but, yeah, lets blame the sign painter    Vous êtes licencié!

And some more French that I the painter can screw up ...

The Good and the Bad/Ugly -- Post-War Dewoitine D.520-based Racers

Two examples of racers developed from surplus Dewoitine D.520 fighter airframes.

(Top) The Arsenal-SNCASE V.S.E.520 racer conversion as first revealed at Châtillon-sous-Bagneux.

The Arsenal-SNCASE V.S.E.520 was joint project between the Arsenal de l'aéronautique and SNCASE (Sud-Est). The V.S.E.520 was built to promote two different products. The first was the Arsaéro 12H, Arsenal's post-war development of the German Junkers Jumo 213 inverted V-12 engine. The second was the cooling arangement (albeit inverted) of the Sud-Est S.E.580 fighter. [1]

Tuned for racing, the Arsaéro 12C (for Course) was to produce at least 2,375 hp. Originally, the VSE.520 was to feature contra-rotating propellers but these were not ready and a 4-bladed prop was fitted instead. That made the racer 'snakey' to handle. But the inverted S.E.580-style cooling proved to the V.S.E.520's Achille's heel.

In the V.S.E.520, the cooling intake scoop was in the belly, the radiator block was mounted horizontally in the fuselage, and the adjustable efflux vent was situated just in front of the enlarged tailplane. In theory, this arrangment should have the same aerodynamic advantages as the that of the S.E.580. But it didn't. The installation proved quite 'draggy' and radiator exhaust air flowing over the tail tended to promote rudder buzz.

As a racer, the V.S.E.520 was a complete failure and was withdrawn from competition before the end of the first season.

(Bottom) The SNCASE S.E.520V racer conversion after the restitution of its metal wingtips. Inset, SNCASE logo (as shown on S.E.520V fin).

Far more successful was Sud-Est's own S.E.520V (for Vitesse). This racer had the same enlarged tailplane as the V.S.E.520 but was powered by a Rolls-Royce Griffon V-12. [2] Most radical was the cooling arrangement.

The S.E.520V substituted the D.520's belly radiator for twin, fuselage-mounted units. Each radiator bath extended along the fuselage-side from behind the cockpit to just below the stabilizers. This arrangement proved highly successful and was believed to produce less drag than a single, enlarged belly radiator.

Nicknamed 'Plus Vite!' ('Top Speed!' or 'More Speed!') by its Sud-Est team, F-DEPV went on to win more closed-course races than any other French post-war air racer.

_____________________________________________

[1] The larger Sud-Est S.E.580 fighter was to be powered by the Arsaéro 24H (a 'doubled' X-24 development of the Arsaéro 12H V-12).

[2] The originally-intended Hispano-Suiza 12Z engine had been rejected as insufficiently powerful.

_____________________________________________

[apophenia]

Time-and-Distance -- the  Coupe de Grande Raid d'Méditerranée

Circuits were not the only 'Unlimited' style of air racing in the post-war era. Time and distance races were also popular. One of the more demanding was the Coupe de Grande Raid d'Méditerranée.

Racers were expected to circumnavigate a lengthy set course around the Mediterranean Sea. This race was an ideal trial for larger, twin-engined aircraft but represented a brutal endurance test for the smaller, single-engined class. Making the challenge even greater was a ban on externally-carried fuel tanks.

The Wooden Wonder finds yet another role

The de Havilland Mosquito dominated the multi-engined categories of European time-and-distance courses. This included the Coupe de Grande Raid d'Méditerranée where the 'Mossie' was the undisputed champion. One racing Mosquito -- G-DHAX -- was directly sponsored by de Havilland Aircraft Ltd. [1] G-DHAX had begun life as a Merlin 113/114-powered B.Mk.35 bomber. Initially, few modifications were made other than the removal of cockpit pressurization and basic demilitarization. Later, an assymetric, low-drag canopy was introduced [2] which radically changed the aircraft's appearance.

Dubbed 'The Spirit of Stag Lane', this appellation was never painted on to the airframe (on instructions from Hatfield to keep markings to a minimum for drag reduction). G-DHAX used standard PR Mossie bomb bay fuel tanks and relied on a coat of carefully applied polish to maintain its high speed.

(Top) G-DHAX as race number '17' (Note: Slipper tanks were for transit only and removed before race time.)

Boulton Paul 'Distance Defiant'

As noted, the most challenging of the Grande Raid d'Méditerranée events was the single-engined course. This too was dominated by the British. The surprise was that the star performers were an aircraft type that few had any regard for during the War -- the Boulton Paul Defiant.

In late 1945, Boulton Paul rebuilt two airframes as 'Distance Defiants' long-distance racers -- G-BPAE and G-BPAG. Both were hybrids consisting of Defiant TT.Mk.III wings and NF.Mk.II fuselage components mated with Rolls-Royce Merlin 70 engines.

The Merlin 70 was a high-altitude powerplant which allowed the 'Distance Defiants' to 'roller coaster' along the race course -- climbing for clear air at altitude before power diving down to pylon height for course turns. This ability to climb high above low-level turbulance and Saharan dust storms gave the Boulton Paul racers a distinct advantage over most of their competitors.

'Distance Defiant' modifications were comparatively modest. A series of fuel tanks filled the forward fuselage while a new cockpit was set in the former gunner's position. That cockpit was covered by a streamlined canopy (which slid aft to allow the pilot to raise his seat for take-offs and landings.

(Bottom) Boulton Paul 'Distance Defiant' G-BPAE after installation of a retractable tailwheel from a  Spitfire Mk.VIII.

____________________________

[1] Somewhat ironically for de Havilland Aircraft Ltd., G-DHAX had been built by Airspeed.

[2] This new canopy was offset to port, covering only the pilot's seat. The starboard seat was removed, leaving the navigator prone in the former bomb-aiming position.

____________________________

[apophenia]

Temps et distance -- Time-and-Distance, French Style

The most radical modifications for the single-engined Grande Raid d'Méditerranée event was the French SuperCobra (F-COBR). The airframe made almost exclusive use of P-63 Kingcobra components gleaned from Armée de l'Air scrapyards. Advantage was taken of the P-63's chassis style of construction. The cockpit module was move aft to sit directly in front of the rear fuselage break point. The engine (a French Hispano-Suiza 12Z-17 -- replacing the Kingcobra's original, mid-mounted Allison V-1710) was moved far forward and drove a Hamilton-Standard 4-bladed propeller from a P-51D through a short extension shaft.

The point of these radical modifications was to free up space for large fuel tanks sitting directly over the aircraft's centre-of-gravity. The concept was proven by a series of Coupe GRM Silver Medals. But the SuperCobra lacked the overall performance to best the Gold Medalist 'Distance Defiants'.

(Top) SuperCobra F-COBR after receiving its revised and lowered canopy covering.

(Bottom) SuperCobra in its original configuration, showing its revised engine placement.

____________________________

[Brian da Basher]

Great stuff, apophenia!

I really like that sleek Distance Defiant! Sure looks built for speed if ever a Boulton-Paul product was!

Brian da Basher

[GTX_Admin]

 :)

[Tophe]

the French SuperCobra (F-COBR).

France was world champion in ugly aircraft, but your French racer is a beauty, wow!

[AXOR]

SuperCobra is sensational !
I'm glad you resumed the D-520 Race theme,fantastic job !

France was world champion in ugly aircraft.

Tophe,I think it's a subjective matter,from my point of view at the end of the 30's Dewoitine D-520,Arsenal VG-33,Potez 630 series  (just to name a few) were beautiful planes.
...in modern times Mirage III,F-1 ,2000,Rafale are beautiful planes too.
Am I right?

[Acree]

I completely agree with Alex.  But... Bloch 200, Potez 540, Farman 221/222/224/225, Amiot 143... and that's just to mention production airplanes.  And don't forget the postwar Potez 75...  I think the French built some of the most beautiful AND some of the ugliest, but certainly the most interesting!

[jcf]

I love the Jabiru and I refuse to be shamed.