Author Topic: Dora experts ... (Read 5113 times)

GScholz · « **on:** May 28, 2004, 09:13:05 PM »

Can you take a look at this site and comment of the validity of the data presented?

http://jagdhund.homestead.com/files/Dora.htm

Some interesting information there, and the author claims to have source documents from Focke Wulf. Also good info on the different power settings.

Batz · « **Reply #1 on:** May 28, 2004, 09:33:20 PM »

Thats BBury's site.. He posts on several forums. I believe Naudet has had contact with him before when he was researching Dora stuff.

I dont know the guy or his sources but he's visible enough in various circles and if the site was a hoax you would have heard about it.

His email is on the site, send him one with your questions...

Batz · « **Reply #2 on:** May 28, 2004, 09:38:26 PM »

Here's an old post from LEMB regarding FW 190 A&D mach numbers..

http://p069.ezboard.com/fluftwaffeexperten71774frm9.showMessage?topicID=46.topic

GScholz · « **Reply #3 on:** May 28, 2004, 09:45:56 PM »

Thanks. I was more looking for fuel consumption data on the Jumo 213A considering how the Dora has become the shortest ranged LW fighter in AH2. If the data on that site is correct then the AH2 Dora burns too much fuel.

Edit: Also, while the F4U4 does get the benefit of water injection to its fuel consumption, the Dora does not.

Batz · « **Reply #4 on:** May 28, 2004, 09:56:13 PM »

In AH2 the Fuel multplier is at x 2. At mil power the d9 has 27 min internal fuel. With wep it burns even more.

RL (fuel mod at 1) it would mean 54 min @ 44.9 MP

There's a thread on the AH2 forums discussing the issue.

http://www.hitechcreations.com/forums/showthread.php?s=&threadid=117803

Batz · « **Reply #5 on:** May 28, 2004, 10:01:31 PM »

We dont know if the AH d9 has mw50 or C3 injection...

According to his site @ Climb and combat power max endurance is 1.33 hours on internal fuel. But its unclear as to what ata and rpm that is...

Batz · « **Reply #6 on:** May 28, 2004, 10:04:13 PM »

Quote

2) Sonder - Notleistung - Special Emergency
I believe this power setting is similar in principle to the Fw190A using "Erhöhte Notleistung" with C3 injection. That is, bleeding of the airline of the blower to induce a petrol surge and use it as a charge cooler. The setting was the same as in the A-8. There was a button, or lever, on the control panel to open the valve. To summarize, it was a petrol injection in the eye of the blower. It had the effect of allowing increased boost by its charge-cooling effect. It could only be used at full speed and 3,250 rpm. It was usable for 10 minutes, This power curve is listed with C3 fuel. I do not yet have a power curve to verify engine output in this configuration but it would be greater than 2100PS based on the speed and climb curves.
After the use of this Special Emergency power, no form of Emergency power could be used for at least five minutes

or

Quote

4) Sonder - Notleistung mit Ladedruckerhoehung mit MW50 u. 1.8 ata. Special Emergency Power (with MW50) 2100PS at 3,250rpm, MW-50 at 150 l/h and B4 at 800 l/h.

Maximum power with MW50 was 2,100 hp at 3,250 rpm and was not to be used above 16,500ft. (around 5000 meters). In any case, the RAE tested the Jumo 213 A-1 with MW50, and at 21,000ft the engine
produced 1680 hp instead of the 1600 hp. At that altitude the output is the same whether you are using Takeoff & Emergency or Special Emergency power. This power setting was to be used for 10 minutes then 5 minutes at normal power before used again. The The Jumo 213A engine power chart also shows a dashed line at 2,240PS.

GScholz · « **Reply #7 on:** May 28, 2004, 10:16:54 PM »

We have the MW50, 377mph at SL Dora.

530 liters/h = 140 gallons/h at "Combat & Climb" according to the site.

AH2 the Dora consumes 156 gallons/h on MIL and 236 gallons/h on WEP.

According to the site on WEP with "Ladedruckssteigerungs-Ruestatz" the Jumo 213A consumed 575 liters/h (151.8 gallons/h) at 3250 rpm. The addition of MW50 would even reduce that number.

Edit: Even the 800 l/h figure you posted is only 211 g/h.

MiloMorai · « **Reply #8 on:** May 29, 2004, 06:05:08 AM »

BMW allowed 12.5% reserve. Did Jumo also use this reserve percentage?

From the Tank bio book,

TO&E - 575l/hr @ 3250rpm
climb - 480l/hr @ 3000rpm
max cruise - 350l/hr @ 2700rpm
above at SL

Batz,

350(l/hr, max cruise) x 1.33(hr) = 465.5l
465.5 x 1.125(reserve) = 523.7l

The Dora held 524l in its 2 tanks.

Something not right with your C&C numbers for at 480l/hr this only gives 0.96hr plus the reserve.

GScholz · « **Reply #9 on:** May 29, 2004, 08:32:32 AM »

In any case the Dora is burning 590.5 L/h at MIL in AH2 (1xFBM), and 893.3 L/h at WEP. Also the Dora had an optional 110 liter / 29.1gal aft fuselage tank. Would be nice to have that considering the outrageous 2xFBM in AH2.

GScholz · « **Reply #10 on:** May 29, 2004, 08:35:19 AM »

Interesting MiloMorai. Perhaps the Ah2 Dora endurance is modelled without taking the 12.5% reserve into consideration.

Batz · « **Reply #11 on:** May 29, 2004, 10:42:12 AM »

That AUX tank hold mw50....

GODO · « **Reply #12 on:** May 29, 2004, 11:03:57 AM »

Quote

Originally posted by Batz
That AUX tank hold mw50....

Correct only if our D9 is not an early one (1900 hp) without MW50. BTW, max AH2 D9 speed is 375 mph. AFAIK C3 was not used for D9s, only B4 + MW50.

Batz · « **Reply #13 on:** May 29, 2004, 11:26:08 AM »

C3 was used on doras.... Read the linkewd site of my reply a few posts up.

Kweassa · « **Reply #14 on:** May 29, 2004, 07:08:18 PM »

What about the aux tanks of our AH 190A-8?

Shouldn't it be just FWD/AFT tanks with the aux tanks filled with C3 injection?