La-5 vs La-7

[Spatula]

Can someone explain what the major differences were between the 5 and the 7. I know the 7 is faster all round, but looking at HTCs graphs, the climb rates are identical.
The speed graphs are nearly mirrors of each other, except the 7 is universally faster.

So, my question is, i guess, is what did they do (Russian designers) to the LA-7 to make it noticeably faster, but not effect the climb rate at all from LA-5fn??? Seems very weird. A more streamlined airframe?? surely that cant be all. I suspect a new/more powerfull engine was added, but it hasnt affected the climb rate in the slightest (according to HTCs graphs)

Are HTCs climb graph for the LA-7 even correct???? HTC??

[Karnak]

They streamlined it, and yes, that is pretty much all.

[Kweassa]

The La-5FN turns a tad better.

[Creton]

I dont know if this is true but I read in some book that theychange fuel loadout of the la7 which resulted in an increase in power to wt. ratio.If I remember correctly it was 3.35lbs./horsepower produced.I 'm no plane buff so I 'm sure this could be wrong.it's hard to beat that 3 cannon la7 though,flew it this morning,cripes that thing is amazingly fast.I still prefer 109's though.I tried an la 5 and it seemed to me that slow speed handling was a little better,but I 'm sure that changes with different pileits.

VIC

[DoKGonZo]

The -7 has the 3-cannon option, which is much better given that the per-cannon RoF is low due to prop sync. This is probably the most critical advantage of the -7.

The -7 is overall faster, but the -5 has better handling - turn, roll, stall - at pretty much all speeds. The lower the speed, the better the -5 feels ... to me anyway.

The -7 can pretty much get away from any prop-plane under 5K alt. The -5 can accelerate quick enough to get out of guns range from just about anything but a -7 or a perk plane, but can't outright get away by virtue of speed alone.

The -5 seems to have slightly better range than the -7, though neither can take drop tanks so the basic range is still pretty low for either.

[1K3]

La-5 has 5 minute WEP limit

La-7 has 10 minute WEP limit

[1K3]

Originally posted by Spatula
So, my question is, i guess, is

what did they do (Russian designers) to the LA-7 to make it noticeably faster, but not effect the climb rate at all from LA-5fn??? Seems very weird.

A more streamlined airframe?? surely that cant be all.

I suspect a new/more powerfull engine was added, but it hasnt affected the climb rate in the slightest (according to HTCs graphs)
 

Lavochkin La-7 is

1. stream-lined La-5FN
2. lighter than La-5FN
3. faster than La-5FN
4. climbed faster than La-5FN
5. longer WEP times than La-5FN (better cooling on La-7?)
6. uses the same engine from La-5FN

TsAGI (Soviet equivalent of NASA) perrfected this already perfect fighter

[Spatula]

Originally posted by 1K3
Lavochkin La-7 is

4. climbed faster than La-5FN
6. uses the same engine from La-5FN

TsAGI (Soviet equivalent of NASA) perrfected this already perfect fighter

Cheers, for that. Im not claiming any expertise in this matter, i'll just point out that HTCs climb charts show an all but identical climb performance for LA-7 to LA-5fn. Except maybe below 5k where the difference is so tiny it may just be the way im reading them.

[Widewing]

Originally posted by 1K3
La-5 has 5 minute WEP limit

La-7 has 10 minute WEP limit

They both have 10 minute WEP Duration... I was reasonably certain of this, but I checked it tonight, getting bored after 7 minutes....

My regards,

Widewing

[Airscrew]

I only have a couple of books with references for La-5/7
La-7
one source says 2,000hp Shvetsov radial another says 1,850 HP Shvetsov M-82FN (ASh-82FN)  
Max speed 413mph, max range 395
or
Max speed 422
Wing span 32ft 1in,  Length 28ft 2in,  Weight 7496lb,  2 or 3 Beresin B-20 (20mm) cannon.

La-5  
1330hp Shvetsov M-82F radial (no other notes)


La-5FN
1,510hp M-82FN or 1,650hp
max speed 403mph
climb rate 5 minutes to 16,000ft
wing area 189 sq ft

Low speed handling is assisted by automatic slats on the leading edges of the wings

I would guess the differences between the La-5FN and La-7 was about 200 to 400hp and probably a cleaner design

[1K3]

Founds some interesting #s for La-7

La-7 in AUGUST 1944
http://www.btinternet.com/~fulltilt/Perform.html#No.452101-39

La-7 in APRIL 1945
http://www.btinternet.com/~fulltilt/Perform.html#La%207%20No.%20452132-76

[justin_g]

Tilt's webpage has the story: http://www.btinternet.com/~fulltilt/deshist.html#1944

[Urchin]

One thing that has always confused me about the La-5 vs La-7.  

If the La-7 is merely an La-5 that has been cleaned up a bit, shouldn't it do *everything* better?  

But in the game, you constantly hear "The La-5 turns a little bit better than the La-7, and it is a little more stable."  

Personally, I never felt a difference... they seemed to handle the same to me, except the La-7 was faster and accelerated better.  

Just curious about IRL performance though.

[dedalos]

Originally posted by Urchin
One thing that has always confused me about the La-5 vs La-7.  

If the La-7 is merely an La-5 that has been cleaned up a bit, shouldn't it do *everything* better?  

But in the game, you constantly hear "The La-5 turns a little bit better than the La-7, and it is a little more stable."  

Personally, I never felt a difference... they seemed to handle the same to me, except the La-7 was faster and accelerated better.  

Just curious about IRL performance though.

Thats because the people in the La5 are willing to turn with you and fight for it.  Most La7s dont even know that they can turn.

[DoKGonZo]

Originally posted by Urchin
One thing that has always confused me about the La-5 vs La-7.  

If the La-7 is merely an La-5 that has been cleaned up a bit, shouldn't it do *everything* better?  

But in the game, you constantly hear "The La-5 turns a little bit better than the La-7, and it is a little more stable."  

Personally, I never felt a difference... they seemed to handle the same to me, except the La-7 was faster and accelerated better.  

Just curious about IRL performance though.

Dunno about IRL, but I personally find the La-5 more forgiving on hard manouevering (esp. at lower speeds) and quicker on the roll rate than the La-7.