What if the Bugatti 100p became a fighter? (1 Viewer)

[Shortround6]

The production version of the He100 had several fuselage changes, enlarged canopy, a conventional cooling system, armed comparable to the Bf109 at the time, was faster and had a better combat radius.

Some of this is questionable.
Fuselage changes happened.
Enlarged canopy happened (most racers would need that) but the claims of "....canopy were slightly redesigned, with the pilot sitting high in a large canopy with excellent vision in all directions." maybe somewhat wishful thinking. No common photo shows a canopy offering anything any better than a Spitfire with a Malcom hood, if that.
The "conventional cooling system" is something of a myth. The cooling system was modified and retracting or semi-retracting ventral radiator was added. This was because the surface cooling system was not up to the task of service use. Both in climb and for ground running. There were other planes that had problems with ground running.
Cooling at high speeds is not that hard although it sounds contrary. What is really hard is cooling while climbing for several minutes or more. Same power as high speed but under 50% of the air flow through the radiator or over the cooling surfaces. On the He 100 they used the rear turtle deck, part of the vertical fin and the horizontal stabilizer as part of the oil cooler system. There was a tank filled with alcohol that had the oil cooler suspended in it and the the alcohol was pumped from the tank to the cooling surfaces and back instead of using a normal oil cooler.
The armament comparable to a Bf109 is questionable. They claimed a single 20mm in the nose and a pair of 7.9mm machine guns but a most (all?) of the export aircraft were delivered with only the 7.9mm guns. While the Germans managed to get a 20mm MG FF cannon into the nose of the early 109Fs that was over a year after the He 100 was in contention. The 109Es never got the 20mm gun in the engine or it was taken back out. It was still jamming too much for service use in 1939 and most of 1940. Heinkel was thinking about trying to put 2 7.9mm guns in each wing root.
No question that the He 100 was faster. With it's low drag it could stretch the fuel more than a 109E.

 

[tomo pauk]

One only has to look no further than the Germany's Heinkel HE 100 race plane to understand why the Bugatti 100P wasn't put into military service. "Although it proved to be one of the fastest fighter [ed. fighter is a generous term] aircraft in the world at the time of its development, the design was not ordered into series production."

There were numerous reasons for this. Key is the fact that it was a racing plane used for propaganda by the Third Reich.

He 100 was initially conceived as a fighter, and then it was turned into a racer. That is opposite than what was mooted with the Bugatti in question, or the original Me 209, that were designed as racers 1st.

... but what is clear, is that at the time the He100 was ready for production, the RLM mandated Messerschmitt build fighters and Heinkel build bombers.

I do recall the RLM had mandated Messerschmitt to build fighters and Heinkel build bombers.

These are quite a sweeping statement.
Me 109 and 110 were being produced in several factories both already before 1940, and that continued through the war. He 111 was also being produced in several factories, among them were two under Heinkel name.
Germans had no problems in having a host of factories making a design deemed worthy - along the three aircraft listed, that applied to Fw 190, Ju 87, Ju 88 etc.
We can also recall that Heinkel was making the He 219 fighters, and MTT was making aircraft as big as Me 323.

The production version of the He100 had several fuselage changes, enlarged canopy, a conventional cooling system, armed comparable to the Bf109 at the time, was faster and had a better combat radius.

As noted by SR6, that was not the case.

It certainly had potential to evolve beyond a dedicated racing machine.

I agree, it certainly had potential.

+1 on these two.

 

[Howard Gibson]

The He100 wasn't ordered into production for reasons unknown, not because of it's racing heritage. Some say politics, some suggest the He100 would deprive the Bf109 program of much needed engines, but what is clear, is that at the time the He100 was ready for production, the RLM mandated Messerschmitt build fighters and Heinkel build bombers.

The production version of the He100 had several fuselage changes, enlarged canopy, a conventional cooling system, armed comparable to the Bf109 at the time, was faster and had a better combat radius.

It certainly had potential to evolve beyond a dedicated racing machine.

What happens if somebody develops a high performance aircraft around a different engine, perhaps a radial engine that Messerschmitt does not want?

There are lots of questions about the He100. Lots of prototypes were doing 400mph in 1940.

 

[GrauGeist]

What happens if somebody develops a high performance aircraft around a different engine, perhaps a radial engine that Messerschmitt does not want?

That would be the Fw190...

 

[TM06]

If you absolutely, truly, genuinely want to make a French racer into a French fighter then the D.550 already has that covered. Hell, It's why it was made in the first place.
The D.55x series are wildly more practical and feasible given that they were based on an already existing combat platform (D.520) on top of being far more conventionally built aircraft in general.
As beautiful as the 100P is, there's no real reason to develop it into a fighter when the D.55x exists.

 

[Shortround6]

Another example of trying to turn a race plane into a fighter is turning the Caudron C.460 into the Caudron C.714 fighter.

Photo of replica. While it won races in Europe and the 1936 Thompson trophy race with only 330hp (?) engine and could hit 310mph at low level, it also was using a wing only 22ft 2 in wide wide with 74.4 sqft of area. Gross weight was about 1930lbs.

By the time they had turned it into the Caudron C.714

The wing area had almost doubled. The weight had more than doubled. Still no armor or fuel tank protection.
The V-12 engine was not race tuned and made only about 60% more power (500hp vs 330hp) than the 6 cylinder engine used in the racer.
The fact that they had to scab a tray under the wing just to hold the 7.5mm machine guns didn't help. Granted the fighter used a canopy where the pilot could actually turn his head
French Air Force didn't want them and they tried to sell most of initial contract to Finland. The ones that made to Finland were used as trainers. Some of the ones left in France were given to 1 Polish group and one training squadron. While the Polish pilots did OK the C 714 was slow, climbed poorly and and strength issues. French Air Force had ordered the C.714s to be withdrawn form service but since the French had no other fighters to issue to the Group as replacements the Polish pilots used the C.714s rather than sit on the ground.
There were a few intermediate steps but the lineage is there.
One of the intermediate steps.

Vision was not a priority in some racing planes.

 

[GTX]

Another example of trying to turn a race plane into a fighter is turning the Caudron C.460 into the Caudron C.714 fighter.
View attachment 833731
Photo of replica. While it won races in Europe and the 1936 Thompson trophy race with only 330hp (?) engine and could hit 310mph at low level, it also was using a wing only 22ft 2 in wide wide with 74.4 sqft of area. Gross weight was about 1930lbs.

By the time they had turned it into the Caudron C.714
View attachment 833732
The wing area had almost doubled. The weight had more than doubled. Still no armor or fuel tank protection.
The V-12 engine was not race tuned and made only about 60% more power (500hp vs 330hp) than the 6 cylinder engine used in the racer.
The fact that they had to scab a tray under the wing just to hold the 7.5mm machine guns didn't help. Granted the fighter used a canopy where the pilot could actually turn his head
French Air Force didn't want them and they tried to sell most of initial contract to Finland. The ones that made to Finland were used as trainers. Some of the ones left in France were given to 1 Polish group and one training squadron. While the Polish pilots did OK the C 714 was slow, climbed poorly and and strength issues. French Air Force had ordered the C.714s to be withdrawn form service but since the French had no other fighters to issue to the Group as replacements the Polish pilots used the C.714s rather than sit on the ground.
There were a few intermediate steps but the lineage is there.
One of the intermediate steps.
View attachment 833733
Vision was not a priority in some racing planes.

And despite those changes it was still hardly effective.

 

[topspeed]

One only has to look no further than the Germany's Heinkel HE 100 race plane to understand why the Bugatti 100P wasn't put into military service. "Although it proved to be one of the fastest fighter [ed. fighter is a generous term] aircraft in the world at the time of its development, the design was not ordered into series production."
[source] Heinkel He 100 - Wikipedia

View attachment 833204

There were numerous reasons for this. Key is the fact that it was a racing plane used for propaganda by the Third Reich. Most important is that racing planes are light weight and built for speed. The HE 100 used a liquid radiator cooling system located in the wings. Any hits to the wings, a large target area to be sure, would compromise the aircraft's cooling system. When it set the speed record, the racing plane had no armor or armament. No armor protection for the pilot, no guns, no bullets and very likely not a lot of fuel. All this this added enough weight that maneuverability and speed became "ordinary". The Messerschmitt Me109, a purpose built fighter, proved superior.

Ernst Heinkel would disagree.

Bf-109 competed with He-112...where as the Heinkel 100-D was a serial production fighter which never was.

He-100D was 100 km/h faster than Me-109 E.

I recall when Heinkel asked about it from Milch he had replied...quatsch....we wre not going to loose this war ( after UK declared war on Germany ) due to a slightly slower fighter....or something similar.



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But about the french fighters...I think Roussel R-30 would have been an absolute winner in 1940.

Roussel R-30 - Wikipedia

en.wikipedia.org

Only about 6 x 8 meters sized fighter.

 

[Howard Gibson]

Ernst Heinkel would disagree.

Bf-109 competed with He-112...where as the Heinkel 100-D was a serial production fighter which never was.

He-100D was 100 km/h faster than Me-109 E.


View attachment 899026

I recall when Heinkel asked about it from Milch he had replied...quatsch....we wre not going to loose this war ( after UK declared war on Germany ) due to a slightly slower fighter....or something similar.



---

But about the french fighters...I think Roussel R-30 would have been an absolute winner in 1940.

View attachment 899027

View attachment 899028

Roussel R-30 - Wikipedia

en.wikipedia.org

Only about 6 x 8 meters sized fighter.

View attachment 899029

Don't compare the He100D with the Bf109E. Compare it with the Bf109F. The speed difference goes way down. The DB601 engines were reserved for Messerschmitt. Heinkel refused to replace the DB601 with a Jumo 211. Was the tested Heinkel He100D in functional combat configuration with armour, weapons, and fuel available to front line units? What manifold boost settings were being used?

I have a fair bit of literature here on He100s. None of it mentions Focke Wulf Fw190s. Fw190s are the new aircraft the Luftwaffe ordered. Focke Wulf were told to not use DB601 engines, and they didn't. The Fw190 was rugged, lacking radiators embedded in the wing skins. The Fw190s quickly became well armed. The He100 would have been useless against American bombers in 1943. Performance? Similar.

 

[fannum]

All of these sexy racers refute the simplistic adage: "If it looks right, it is right!"
Just look at the dozens of '50s Air Force whiz-bang projects ala F-88, F-95, F-102, F-104, B-58, etc. etc. that were exciting and looked good in ads and airshows but failed when put to the test.

 

[tomo pauk]

Don't compare the He100D with the Bf109E. Compare it with the Bf109F. The speed difference goes way down.

The fellow member was right to compare the He 100 with the Bf 109E - these two used the same engines. Granted, the Heinkel's speed figures need to be taken with he salt, but the 109E was one draggy aircraft.

Heinkel refused to replace the DB601 with a Jumo 211. Was the tested Heinkel He100D in functional combat configuration with armour, weapons, and fuel available to front line units? What manifold boost settings were being used?

There was no leeway with the boost settings on the DB 601 in the military trim (ie. when using normal B4 fuel) to begin with. You are right to point out the state of the He 100 - the numbers of 670 km/h were Heinkels', not RLM's - further complicated with absence of any test results.
FWIW, Soviets stated 650 km/h for the He 100 they bought, that was supposed to be armed with 3 MG 17s. Probably no armor what so ever.

Focke Wulf were told to not use DB601 engines, and they didn't.

Were they told so?
IMO, FW company looked at the promissed power figures of the BMW 139 (~1450 HP at 5 km), and were confident that by keeping the fighter small, some inovative nose job and with using the plenty of exhaust thrust they will have a 680 km/h fighter. In reality, the early Fw 190s, that differed a lot vs. the initial design, did about 650.

The Fw190 was rugged, lacking radiators embedded in the wing skins.

Very true.

The Fw190s quickly became well armed. The He100 would have been useless against American bombers in 1943. Performance? Similar.

A ~650 km/h 1000-1100 HP fighter of 1939/40 should have gotten much faster with engines of 1943. See how much the Italians gotten with the restricted DB 605A on the MC.205, let alone the Soviets with the obsolete VK-105 engine on the diminutive Yak-3.
The He 100 with the 'normal' cooling system and resonable updates should be a replacemnent for the Bf 109.

 

[Howard Gibson]

The fellow member was right to compare the He 100 with the Bf 109E - these two used the same engines. Granted, the Heinkel's speed figures need to be taken with he salt, but the 109E was one draggy aircraft.

In 1939, the Bf109E was a production aircraft with manufacturing facilities, and logistical support. Getting the He100 into service meant building factories and logistics. The He100 was a prototype, comparable to the Lockheed P38s, Vought F4U Corsairs, Hawker Typhoons/Tornados, and Fw190s.

 

[tomo pauk]

In 1939, the Bf109E was a production aircraft with manufacturing facilities, and logistical support. Getting the He100 into service meant building factories and logistics. The He100 was a prototype, comparable to the Lockheed P38s, Vought F4U Corsairs, Hawker Typhoons/Tornados, and Fw190s.

He 100, as a prototype, is earlier by a year or two than these aircraft. It was also a much simpler & smaller aircraft than either of these (including the engine chosen), probably only the Fw 190 coming in close in that regard.
Germans (RLM, Goering, Udet, etc) will need to make a decision to go with He 100 in production, in order for that fighter to have an impact on the war. By the time prototype Typhoon or the XF4U took the 1st flight - early 1940 - it is not unreasoneble to expect the 100 would've been in series production that way.

 

[topspeed]

He 100, as a prototype, is earlier by a year or two than these aircraft. It was also a much simpler & smaller aircraft than either of these (including the engine chosen), probably only the Fw 190 coming in close in that regard.
Germans (RLM, Goering, Udet, etc) will need to make a decision to go with He 100 in production, in order for that fighter to have an impact on the war. By the time prototype Typhoon or the XF4U took the 1st flight - early 1940 - it is not unreasoneble to expect the 100 would've been in series production that way.

Unfortunately for Germany....Ernst Heinkel woke up too late with Meredith ettect...on his little racer.

670 km/h was unheard of in 1940:

Heinkel He 113 - Wikipedia

en.wikipedia.org

 

[GrauGeist]

Unfortunately for Germany....Ernst Heinkel woke up too late with Meredith ettect...on his little racer.

View attachment 899099

View attachment 899100

That drawing is not the production model, as it shows the evaporative cooling panels.

The He100 intended for production had the retractable "dust bin" radiator (like the KI-61) in the ventral position just aft of the cockpit.

 

[topspeed]

That drawing is not the production model, as it shows the evaporative cooling panels.

The He100 intended for production had the retractable "dust bin" radiator (like the KI-61) in the ventral position just aft of the cockpit.

Yes the Heston racer type cooling may be a fan product.

Did He-100D have anykinda range ?

 

[GrauGeist]

As much as I like the He100 (I truly do), it was simply too small to have any future in the European air war.

It did not have the room for heavy weapon upgrades that would be needed after 1943 due to it's compact size.

To be honest, the He112B would have been the better choice for the RLM to request production. It had a larger airframe, longer range than the Bf109 (with comparable speed profiles) and the ability to be upgraded as situations dictated.

 

[topspeed]

As much as I like the He100 (I truly do), it was simply too small to have any future in the European air war.

It did not have the room for heavy weapon upgrades that would be needed after 1943 due to it's compact size.

To be honest, the He112B would have been the better choice for the RLM to request production. It had a larger airframe, longer range than the Bf109 (with comparable speed profiles) and the ability to be upgraded as situations dictated.

Seems that 100D had 300 km more range than Me 109 E:

The combat range of the Heinkel He 100D (He 100D-1) was approximately 900 to 1,000 km (about 560 to 624 miles). [1, 2, 3]

• Combat / Normal Range: 900–1,000 km (560–624 miles)
• Imperial Equivalent: ~559–624 miles

 

[tomo pauk]

The He100 intended for production had the retractable "dust bin" radiator (like the KI-61) in the ventral position just aft of the cockpit.

All He 100s - both racers and fighters - were with the retractable auxiliary radiator, vs. the Ki 61 having the fixed one.
Unfortunately, the good info about the planned 'real', series-produced He 100 fighters is pretty much absent, being replaced with the post-war myths.

As much as I like the He100 (I truly do), it was simply too small to have any future in the European air war.

It did not have the room for heavy weapon upgrades that would be needed after 1943 due to it's compact size.

Probably no worse in that regard than the Bf 109 - talk, three cannons tops? A MK 108 in the Vee should come in handy, while ackonweldging the bad ballistics of it. There is also a lot of the air war in the MTO and the East to do.
Vs. the Bf 109F/G, it should've been a bit faster with the same engine, and with a much better undercarriage, to the joy of the low-time pilots. Replacing the surface coling with normal cooling will also free a lot of the internal volume.

To be honest, the He112B would have been the better choice for the RLM to request production. It had a larger airframe, longer range than the Bf109 (with comparable speed profiles) and the ability to be upgraded as situations dictated.

How big was the He 112B actually?
Much of it's range came from the fact that it used one of the most frugal, and in the same time, least powerful V12s of the day. Swap the engine to the DB 601, add extra cooling capacity and it's 300-something liters of fuel becames a bad joke.

 

[Shortround6]

He 100 was too small.
Very good for performance. Not so good at being an effective fighter, especially after the summer of 1940 when protected fuel tanks and armor came into fashion.
He 100 didn't have enough volume to put in things like fuel, guns/ammo and cooling system/s. It had very low drag, in large part because they used a lot of volume spreading the cooling system/s all over the place in the plane.
This makes it very hard to figure out what a 1941 or 1942 version would have looked like or performed.
I can accept either a 20mm MG 151 in the prop and two 7.9mm guns in each wing (four total) or even a MK 108 in the prop.
Putting cannon in small wings is hard. You can do it by redoing the spar/s and adding lumps and bumps of various sizes but then the drag goes to hell. You can use pods but again the drag goes to hell. Putting a pod under each wing of a P-39 or P-63 is one thing, they were fairly large aircraft. Putting similar pods under a much smaller aircraft is a higher percentage of the drag total. It is certainly going to affect the power to weight ratio (climb) and wing loading (turn) more.
Going to protected tanks is a problem, a lot depends on the degree of protection actually wanted. CO2 systems or exhaust gas are light weight and can reduce fires, they don't do anything for getting the plane home when it is leaking fuel at more than a trickle. Using coatings on wing tanks means decreasing the volume of the tanks if they fit in the same space.
He 100 tanks were behind the main spar in an increasing thinner part of the wing. Adding tanks further outboard gets diminishing returns and may hinder roll response.
You can ditch the surface cooling (thing really big target for the enemy to hit) and go conventual but then you have higher drag.
You can easily beat the 109E, the question is beating the 109F. Granted the 109F was bit later in timing but the He 100 has less growth potential. He 100 has the wing loading of an early 109F.
In 1939 and much of 1940 the MG FF cannon was not working in the through the hub mounting. They got it to work in the very early 109Fs.
A 3 gun or 5 gun He 100 with all 7.9mm guns for most of 1940? assuming they can keep the through the prop 7.9mm gun working in 1939/40.
It is possible to put 20mm guns in the wings of He 100 but what has to be sacrificed to do it? Wing root like Fw 190 but in smaller wing? Lumps and bumps?
Outside the prop arc but that means the gun breeches are right in the middle of the existing fuel tank/s. They can be moved but wing guns and fuel further out in the wings is going to hurt roll response.