Lavochkin question

[pipz]

I enjoy flying the LA5 a bit but its legs are realy short.So my time flying them are shorter than Id like.I took up the LA7 the other day and it seems its range is a lot better than the 5.Now maybe this is just my imagination.Does anyone have figures on the range of these planes?From what ive read the La5 should have better range than the 7.

Thanks
Pipz

[Karnak]

La-7 has less fuel than the La-5FN, but the same engine.  Fuel consuption should be the same.  Range might be equal due to greater speed, but endurance is less.

[Blooz]

As soon as you take off cut back on the manifold pressure and the rpm's to cruise settings. It will double your range.

[Ghosth]

Wep climb to 8k, once level pull rpm back to 2100 or so. Cruise to the fight. After I've made a couple of passes run the rpm back up again. Stay off the wep if you can, its a gas guzzler.

With a bit of practise shouldn't run out of fuel more than once a tour or so.

[Tilt]

Originally posted by Karnak
La-7 has less fuel than the La-5FN, but the same engine.  Fuel consuption should be the same.  Range might be equal due to greater speed, but endurance is less.

The La7 could carry 2 litres more fuel than the La5FN due to its centre tank being 170 litres to the La5FN being 168 litres.  Both had 2 x inner wing tanks of 148 litres each. (with a small filing cup/tank of 2.5 litres each which was not counted toward total capacity)

Fuel was fed gravimetrically (via non return valves) from the wing tanks thru the centre tank so if the centre tank sprung a leak then all tanks drained.

The La7 endurance was the greater for the same flying conditions.

I can show you endurance figures that vary wildly across many publications (especially for the La5FN).

Early La5's had a 5 tank set up giving 548 litres (centre @ 124 + 2 x 114 + 2 x 98 outer wing) Even in the La5 series of 1942 the outer wing tanks were removed to save weight. However space for these tanks remained in all the wooden sparred designs which included the La5FN's produced in 1943.

For max Lavochkin endurance in AH climb to 17500 where you have max manifold pressure/rpm whilst in the 2nd stage of boost. The throttle back to Man 30 at 2200 rpm

[pipz]

Thanks for the input fellaz!

Tilt...Im glad you mentioned that the figures vary over publications.In the one book I have it says the la5 had better range.Ill have to check the other book I have on Lavochkins and see what they say.


Pipz

[bj229r]

What Blooz said--even on max cruise settings Lghay is faster than most planes

[Viking]

In this game both planes have the same engine and carry 122 gallons of fuel. They should have the same loiter time, but the La-7 should have better range due to its greater speed.

[pipz]

Thanks for the input Viking.I thought the higher speed of the 7 was what was making the diference.Your covering more ground for the same amount of gas.

Thanks
Pipz

[splitatom]

i belive the soviets actualy did fit drop tanks retrofiting the bomb with drop tanks and adding a fuel line that drained into the wing tanks:O

[SEseph]

LA5 and LA7 basically the same in feul consumption, so this works for both. Here's all my findings:

LA has aprox 20-25 mins of fuel @ 100%. The level speed is about 350mph.

Cut RPM's back to 1800, and look at it... You'll maintain a speed in excess of 225mph AND have over 80 mins of fly time. The higher you get, the easier on the engine, and you can actually see your time go UP. I've proven this on many missions with Falcon23 and thndrEGG. We go 4-5 sectors to target, climbing with bombers to 20k, fight, and return home. When I land, I have fuel to spare, while not much, it gets me home. OH to those who are going to comment on this.. I do max my speed when in combat.. better to save my life than my fuel.

Also, to ensure good alt/speed/fuel when getting to a target that is close, upon take off, go level, set speed to 275, then auto climb when you hit 275. You'll hold a climb rate of about 2.5k and still scream over there. at 300mph you maintain  1.4k and so on. LA's might be usable by all, but most have no clue about how to truly use them.

[SEseph]

Originally posted by SEseph
LA5 and LA7 basically the same in feul consumption, so this works for both. Here's all my findings:

LA has aprox 20-25 mins of fuel @ 100%. The level speed is about 350mph.

Cut RPM's back to 1800, and look at it... You'll maintain a speed in excess of 225mph AND have over 80 mins of fly time. The higher you get, the easier on the engine, and you can actually see your time go UP. I've proven this on many missions with Falcon23 and thndrEGG. We go 4-5 sectors to target, climbing with bombers to 20k, fight, and return home. When I land, I have fuel to spare, while not much, it gets me home. OH to those who are going to comment on this.. I do max my speed when in combat.. better to save my life than my fuel.

Also, to ensure good alt/speed/fuel when getting to a target that is close, upon take off, go level, set speed to 275, then auto climb when you hit 275. You'll hold a climb rate of about 2.5k and still scream over there. at 300mph you maintain  1.4k and so on. LA's might be usable by all, but most have no clue about how to truly use them.

1800=18000 and manifold must be set to 25 or 30 sorry, was tired.

[Viking]

At 18000 rpm the engine would fly apart. I guess you really meant 1800 after all.

[Tilt]

Originally posted by splitatom
i belive the soviets actualy did fit drop tanks retrofiting the bomb with drop tanks and adding a fuel line that drained into the wing tanks:O

I have no record of this..........there are pictures of Lagg3's (same wing as the early la5FN) with drop tanks but even these are "experimental".

I have never seen a picture of any la5/7 with drop tanks fitted.

Further the outer tanks drained gravimetrically to the fuselage tank (by gravity)

Hence to use drop tanks  mounted off the wing bomb points additional fuel pumps may be required.

[SEseph]

Originally posted by Viking
At 18000 rpm the engine would fly apart. I guess you really meant 1800 after all.

hehe guess so.. 18 though is the magic number