He-100D weight

[Piper106]

There seems to be serious differences in the quoted empty weight for the He-100D-1, the version with armament/military equipment.

William Green in volume 1 of the classic 'Fighters - War Planes of the Second World War' gives the empty weight as 2075 kg / 4563 pounds. Wikipedia and other internet sources give an empty weight of 1810 kg / 3990 pounds. That is a lot of difference.

Is this another case where Green was not working from original source documents and better data has become available since his research. Or was Green correct, and the later authors are quoting the weight of the lighter 'racing' versions of the He100 that lacked military equipment???

If the 1810 kg weight is correct, the He 100 was the lightest '1000 HP' fighter of WW2.

 

[davebender]

That's to be expected when dealing with prototype aircraft. Designer implements many changes to see what works best so they are all a little different. Even the same prototype can vary in weight as changes are implemented during testing process.

 

[krieghund]

You've come to the right place. This is the Datenblatt for the He100 V4 which in most documents say it was the first model to be equipped with armament. This is supposedly the first so equipped for the production models that came after it. I also have the V-5 datenblatt but I believe it is without armament. However I have tons of docs I can sift thru. The Armament was an engine mounted 20mm MG/FF and two wing mounted 7.9mm MG17 in the wing roots. I have a blueprint which shows a MG151 mounted to the engine as well. However the aircraft wasn't really ready for combat as it wasn't rung out and it had no armor nor SS tanks. There were also plans to enlarge the wing and install the DB601N and DB601E engines.

Also it I believe has been shown that the "D" suffix given is an after war creation. There were three distinct production aircraft deliveries with minor variations between the lots. All three contracts are referenced by series I, II and III with the suffix "A". Also the only ones without the standard evaporative cooling were one or two test aircraft at Rechlin after production used as prototyping aircraft. At least two others were used as chase aircraft at Rechlin for the jets being trialed there.

Anyway this datenblatt should give an insight into the weight loading and performance of the aircraft. This also has the lower altitude rated DB601A and production aircraft had the DB601M at 4500m so the performance would be slightly better for the He100A models.

 

[davebender]

Lists every He-100 airframe built and describes changes as design evolved.

Early prototypes.
V1, V2, V3, V4, V8
.....V8 was replacement for V3 which was destroyed in a test flight. Used in speed record attempt. Then a museum aircraft.
.....V1, V2 and V4 sold to USSR May 1940.

Block 1 prototypes.
V5, V6, V7
.....All sold to USSR May 1940.

Block II prototypes.
V9, V10, A06 through A014.
.....3 of these airframes were sold to Japan during Summer 1940.

Block III pre-production aircraft.
A015 through A025.
.....Not all completed but exact number unknown due to Heinkel records destroyed in bombing raid.
.....It is estimated that 16 or 17 total AO series airframes were completed.
.....RLM paid Heinkel 92,600 for each O series airframe. These are hand made aircraft, not mass production.

 

[davparlr]

Ray Wagner in "German Combat Planes" shows an empty weight of the He 100D-1 as 2100 kg (4623 lbs).

 

[krieghund]

Its only 3 kg off from the V4 datenblatt. Of course as said before I haven't seen any wartime docs with the "D" suffix. Here is the flight test report for 1st flight of V5. It appears not to have armament installed but has the DB601M installed and its empty weight is 2045kg,

 

[tomo pauk]

Thanks for the stuff, man

 

[davebender]

We can only speculate.

Evaporation cooling system must be replaced with conventional radiators before RLM will accept the aircraft. A major engineering change as existing plumbing for cooling system would be removed. Would conventional radiator(s) be lighter or heavier then existing system? In any case this change will probably lower production cost.

Did any of the prototypes have self sealing fuel tanks, bullet proof windscreen or armored pilot seat? These things all add weight.

Even the engine changes slightly. Production aircraft would have a normal DB601 engine rather then special version designed to interface with evaporation cooling system.

Perhaps all these changes are the reason Hungary opted for He-112B over He-100. He-112B was production ready and He-100 was not.

 

[DonL]

We can only speculate.

Evaporation cooling system must be replaced with conventional radiators before RLM will accept the aircraft. A major engineering change as existing plumbing for cooling system would be removed. Would conventional radiator(s) be lighter or heavier then existing system? In any case this change will probably lower production cost.

Did any of the prototypes have self sealing fuel tanks, bullet proof windscreen or armored pilot seat? These things all add weight.

Even the engine changes slightly. Production aircraft would have a normal DB601 engine rather then special version designed to interface with evaporation cooling system.

Perhaps all these changes are the reason Hungary opted for He-112B over He-100. He-112B was production ready and He-100 was not.

Dave your statement is wrong! The He 100D-1 was without evaporation cooling, she was flying with a normal radiator.

To the weight issue:

Empty weight without weapons was 1810kg
Empty weight with weapons (Rüstgewicht) was between 2010 - 2090 kg

 

[davebender]

They were all prototypes. Which prototype number do you consider to be "He 100D-1"?

 

[GrauGeist]

"White 5" that was part of the EHF defense force, is usually referred to as a D-1, this was in 1940

 

[davebender]

The authenticity of two EHF type sheets dated 1939 and describing, respectively, "D-0" and "D-1" variants has recently been called into question; two leading authorities on Heinkel aircraft have agreed to disagree regarding the dating and contents of the documents.

Hmmm.

He-100 D-1 "White 5". 1 August 1940.

Better known to the world as the "He-113", White 5 formed the basis for a series of propaganda photographs which hinted at the He-113 entering service with the Luftwaffe as a day and later as a nightfighter.

Factory Defense Force.

An aerial photograph of the Marienehe factory airfield showing at least five He-100s.

The EHF defense force consisted of late production prototypes (A0 series airframes). No proof White 5 was part of the force but it's possible.

A0 series aircraft spinner was designed to accomodate a cannon blast tube. Removable bipod for pilot head armor. Fuel capacity increased to 420 liters. Standard Revi 12 gun sight.

Early model prototypes exported to USSR had a single MG 17 in each wing. Probably retained for A0 series in addition to hub cannon.

 

[krieghund]

Here are several flying shots showing the ventral radiator retracted. It was needed on the ground as there is not enough airflow over the evaporators for sufficient cooling. Somewhere I have a document that lists the spurious markings to the airframe Wkr. I only have one picture I believe is at Rechlin of a He100 with what appears to be a scoop under the left wing for a possible auxiliary radiator. Of the six He100 delivered to the USSR WKr 3006 had three MG17s equipped at delivery and I have included a drawing of the arrangement. As to the "D" reference applied to the aircraft it is interesting to note that in the Rechlin Doc shown here where the He100 is described in its only real operation role as a chase plane to the jets being tested there it is only referred to as the He100.

 

[GrauGeist]

From what I've read, the "D" series were the last modified versions with the larger radiator and slightly widened wings. The D-0 and D-1 (about 12 total) were stationed at EHF as defense aircraft, though none were ever reported to have seen combat.

 

[krieghund]

I do have a line drawing of the expanded wing size but the author has not given permission to distribute as it will be used in Vol 2 of Erwin's book. These copies discuss the contract and deliveries of the A series aircraft. They also include the serial construction documents.

 

[davebender]

Radiator was only a supplement. Evaporative system was still primary cooling method.

Erwin Hood states lack of confidence in cooling system is primary reason He-100 was rejected for production. Otherwise most comments about the aircraft were positive.

If Heinkel had built the aircraft with Me-109 style wing radiators it might have become the Luftwaffe's "second iron in the fire" for Jagdgeschwader. Why was Heinkel so determined to stick with the novel cooling system?

 

[Shortround6]

Without it the performance advantage takes a hit to the head.

Performance may still have been better than a 109 but with a conventional cooling system the difference in performance would have been a lot closer.

 

[davebender]

Luftwaffe and most others who operated Me-109 were happy with performance. He-100 with normal cooling system need only be as good and as inexpensive to mass produce. It doesn't need to be superior.

 

[DonL]

Indeed shortaround6!

The He 100D with normal radioter but with the DB601M (1175PS) managed something about 640km/h (different sources from different books), the Bf 109F with the DB 601N (1200PS) managed something about 620 km/h. So your summery is very correct.

 

[tomo pauk]

At what full throttle altitude the DB-601M and DB-601N were developing how many PS?