Author Topic: Bombs on Yak-9u  (Read 904 times)

Offline Tilt

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Bombs on Yak-9u
« Reply #30 on: September 11, 2002, 02:03:23 PM »
Quote
Originally posted by Vermillion


My understanding on the engine is that the WWII version of the engine of the Yak-9U was the VK107, the VK107A was introduced after the war which had water injection I believe (or some other form of WEP). The Korean vintage Yak-9U used the VK107A.    


Its my bad........... the figures for the Yak 3 given were the VK107 -A figures and the only ones given for the VK 105 PF-2 are stated as 43 therefore they are prototype.............

G& K also wrote Soviet Combat Aircraft V I & II where one finds the same numbers..............

VVS test data usually show the test pilots name whose name/s is on your data??? if its a certain Major AG Kubyshkin then it will be relevant. (he also did the bulok of the La7 trials)

to correct my data for the prototype Yak 3 VK 105 PF-2

1) Yak 3 wings break at moderately high G

2) faster climb to 16400ft (yak 3=4.1 mins yak9U=5 mins)

3) slower at sea level Yak 3 =565 km/hr, yak 9U= 575 km/hr.

4) slower at 5000 m alt (a bit)

5) longer range 850 km v 675 km

6) less wing area 14.85 v 17.11 (roll rates?)

7) better std turn 19 v 20 secs

So this shows a comparatively (but slightly) better turning, climbing, accelerating, rolling AC with  a tad slower top speed and a delicate disposition.............

Given it was lighter (and less power full) its dive accel will be less IMHO. But it may show a bit less drag allowing it to hold e a little easier.

I have translated the tables so if you want some help send me some copies...................alth ough I am sure we have folk here who can read Russian
Ludere Vincere

Offline Vermillion

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Bombs on Yak-9u
« Reply #31 on: September 11, 2002, 04:17:58 PM »
Picked up my "Soviet Combat Aircraft " when I got home and found this.  Incidentally, they say that the VK107 was the "A" in the Yak-9U  *shrugs* I'm not sure.

In regards to your earlier questions
page 157.  "Tests carried out at the NII VVS at the end of 1944 and the begining of 1945, using an Omsk series -production  Yak-9U, showed that  most of the defects mentioned earlier had been overcome.  Speeds of 357mph (575 km/h) at ground level and 417mph (672 km/h) at 16,400ft (5km) were reached, close to official requirements".

And I'm sure you'll notice that this matches the data Pyro used in our Yak-9U.  Imagine our Yak-9U with "prototype" data, which is 20mph faster at all altitudes 372 mph at SL and 434 mph at 16k. Muahhahahhaha ..... oooops sorry ;)

I would LOVE to see a Yak-3 with either the VK107 or Vk108 powerplant. Both were real beasts at 446 mph and 463 mph respectively at altitude.  :)  But admittedly, most if not all were the 105PF.  I did find one source a long time ago that said that approximately 100 Yak-3's with the 107 saw combat before the wars end, but evidently they were really rare if they existed at all, and the VK107 production was prioritized to the -9U's.  And I was never able to confirm that from other sources.  Maybe the new book will have something more

Offline Tilt

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Bombs on Yak-9u
« Reply #32 on: September 12, 2002, 03:46:56 AM »
Quote
Originally posted by Vermillion
Maybe the new book will have something more



It does not......... I have it.......... what it adds to Soviet Combat Aircraft is more narrative on the AC's front line history and a rewording of the text.

More pictures

More graphics

Bit more on non USSR and post war usage.

indeed the data table at the end is missing the so called yak-3 1943 column..........I suspect for good reason.
Ludere Vincere