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General Forums => Aircraft and Vehicles => Topic started by: Laika on February 03, 2001, 05:33:00 AM

Title: La7 ..how does it rate ?
Post by: Laika on February 03, 2001, 05:33:00 AM
I was wondering how the La7 rates against the La5 and other rides in the main arena ?

Am I close in thinking it’s a La5 with some refinements that make it faster, has 3 faster firing 20mm instead of 2 slower, A bit less range, better hi alt performance, under wing rockets as a option. (anything else ?)

Leonid how much impact do think the La7 will have on the main arena ? I don’t have any spec’s that I’d call reliable for Russian fighters ver the rest. Faster and with a extra cannon sounds to good to be true  (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)  

Laika
Title: La7 ..how does it rate ?
Post by: Hans on February 03, 2001, 06:54:00 AM
The information I have on the La-7 says that it is a refined La-5FN.

Its manufactured with less wood and more metal as part of the fuselage, and changes in the airframe and wing shape.  It has the same engine as the La-5FN.  Extenally you can see the small air intake above the engine is gone.  This should inprove forward visibility a bit.

Bassically its a lighter, more areodynamic version of the La-5FN.

Armament is the same as the La-5.  There were two Lavochkin factories.  One built their aircraft with two 20mm Besin cannons (the La-5 we have comes from this factory), and the other factory built their Lavochkins with three cannons (one side was a twin mounting).

Hans.
Title: La7 ..how does it rate ?
Post by: leonid on February 03, 2001, 07:34:00 AM
The La-7 is basically a La-5FN that has been aerodynamically refined, and lightened.  The B-20 cannons were much lighter than the ShVAKs, so much so that three B-20s with 450 rounds was no heavier than two ShVAKs with 400 rounds.  About 200 B-20 La-7s saw action late in the war, all the rest being armed with two ShVAKs.

The combination of aerodynamic refinement and lightening of the airframe resulted in an average speed increase of 15-20mph(24-32km/h), improved performance, and higher performance ceiling.  In terms of AH, this means the La-7 should perform like a Yak-9U, except be noticably faster.

[This message has been edited by leonid (edited 02-03-2001).]
Title: La7 ..how does it rate ?
Post by: Laika on February 03, 2001, 08:01:00 AM
So is there any news if the AH La7 will be the 3 cannon model?
Title: La7 ..how does it rate ?
Post by: leonid on February 03, 2001, 09:20:00 AM
I was told by HTC that the 3 gun loadout would be available.
Title: La7 ..how does it rate ?
Post by: Vermillion on February 03, 2001, 10:45:00 AM
 
Quote
In terms of AH, this means the La-7 should perform like a Yak-9U, except be noticably faster.

Well... Yes and No.

If we go by the "production" performance of the La7, which is the performance used for the FM in Aces High for the La5Fn and Yak-9U, the La7 will be faster than the Yak-9U on the deck but will be slower at altitude.

Some important performance figures (La7 numbers are for the x3 cannon version), all taken from the same source for comparability. Source: Soviet Combat Aircraft of the Second World War Vol 1. By Gordon & Khazanov (FYI which match the numbers on current La5FN and Yak-9U in AH exactly)

                    La5FN     La7     Yak-9U
Horsepower           1470      1470    1500
Wing Area(sq ft)     189.3     189.3   184.6
Gross Weight(lbs)    7,323     7,308   7,036
Speed at SL (mph)    356       381     357
Speed at Alt(mph)    385       411     417
Climb to 5km(min)    4.7       5.3     5.0
Turn Time360(secs)   19        20.5    20
Op. Range (miles)    360       413     419

So basically the La7 is a comparable counterpart to the Yak-9U. The La7 will have better deck speed and better guns, while the Yak-9U will be better at altitude and have better visibility. Otherwise, they are very similar.


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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: funked on February 03, 2001, 01:09:00 PM
An asterisk for Verm's post:  
The Gordon and Khazanov tables show the normal power of the M-82FN engine, which is 1,460 hp at 15,250 ft.  The augmented takeoff power (WEP) was 1,850 hp.

This aircraft is about 1500 lb lighter than a Fw 190A-5 but with 150 more hp.   (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif)

[This message has been edited by funked (edited 02-03-2001).]
Title: La7 ..how does it rate ?
Post by: leonid on February 03, 2001, 11:41:00 PM
Verm,
My data is not from that book, but from official NII VVS records.  The max speed results I posted(in another thread) were taken from a serial production La-7(#45213276, plant No.21) in April 1945.

[This message has been edited by leonid (edited 02-03-2001).]
Title: La7 ..how does it rate ?
Post by: Vermillion on February 04, 2001, 09:01:00 AM
I know Leonid, I was just saying that since both the La5FN and Yak-9U match the Gordon and Khazanov tables, I was using the similar tables as a reference point.

Hey... no arguements, I would enjoy the improved performance of your documents.

But given Pyro's past history on the whole "prototype/production" issue (which is a misnomer anyway due to translation issues IMO), I figure that the VVS planes will always get the "dirty end of the stick"  (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)

**Pyro smacks Verm in back of head**  (http://bbs.hitechcreations.com/smf/Smileys/default/tongue.gif)

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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: brady on February 04, 2001, 10:05:00 AM
 Aside from the refinements mentioned above, the Ospery Enclyopedia of Russian Aircraft mentions the following improvements over the La-5FN:

Better propeller blades and hucks dogs , improved cockpit,gyro horizon,better radio tuning, improved reflector sight(PBP-1B(V))apparently entered service in May of 44...Production terminated early 46 at 5,753 planes(kinda seams like more than just a couple hundred saw service, the book also states that several units used the La-7 in combat and many famous aces got their kills in it.


 
  After all is said and done I am very happy to see the La-7, it was a favorite of mine in FA II and I kind of missed it, also it will have rockets (I hope) so will give the VVS a little more punch    (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)

Brady

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   (http://content.communities.msn.com/isapi/fetch.dll?action=MyPhotos_GetPubPhoto&photoId=nHwCwcDEJznXbXfCxAJfgD0a7w1sDVrWuMP28UBOabRCH339Yvya3KrR2Q8UMjrBJ)  

[This message has been edited by brady (edited 02-04-2001).]

[This message has been edited by brady (edited 02-04-2001).]

[This message has been edited by brady (edited 02-04-2001).]
Title: La7 ..how does it rate ?
Post by: Wotan on February 04, 2001, 11:30:00 AM
no mention of climb rate?...... fa2's la7 would climb forever without stall i know fa2 fm was porked beyond pork but does anyone have climb stats?

(edit) i'm blind i see it in verm's chart hnx anyway

[This message has been edited by Wotan (edited 02-04-2001).]
Title: La7 ..how does it rate ?
Post by: Jekyll on February 05, 2001, 04:01:00 AM
Hmmm interesting.  The La7 has the same wing area as the La5, the same engine output, and is a few pounds lighter, yet climbs to 5 km slower than the La5 and does not turn as well.

Anyone have an explanation for that?

------------------
=357th Pony Express=
Aces High Training Corps
Title: La7 ..how does it rate ?
Post by: Duckwing6 on February 05, 2001, 06:04:00 AM
Ok now how do i fight one in my D-Hog ?  (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)

DW6
Title: La7 ..how does it rate ?
Post by: Vermillion on February 05, 2001, 07:07:00 AM
Duck, its real simple  (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif) stay above 15k, or you die  (http://bbs.hitechcreations.com/smf/Smileys/default/tongue.gif)

The biggest weakness of the La7 is also the biggest weakness of the La5FN, altitude. Anything above 15k and you might as well forget it, and to be really honest you can notice the performance loss at just 10k. The one reason I may stick with the Yak-9U is that it will stay competitive up to 20k and fightable up to 25k, while the La5/7 suffers at the 10/15 I mentioned above.

Jekyll, I wondered the same thing. The only thing I can think of is just a normal variability in performance from aircraft to aircraft, and pilot quality/familiarity. Good Question.

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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: aknimitz on February 05, 2001, 10:33:00 AM
Why exactly is it that the La5/7 perform poorly above 15K?  I have not really noticed, but then again most fights I have with the la5 are below 10K.

Nimitz
Title: La7 ..how does it rate ?
Post by: Dingy on February 05, 2001, 11:31:00 AM
Hmmmm...dunno about your La5 but mine fights pretty well up to 15K.  Anything higher, I just bait em down to my level  (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)

Higher than 15K, Verms right...its tough to do much.

-Ding
Title: La7 ..how does it rate ?
Post by: leonid on February 05, 2001, 11:55:00 AM
Actually, there are better times than that for climb and turn rates for the La-7.  However, there are also those times for some serial production La-7s.  For example, a serial production La-7 posted a time of 4.65min(nominal)/4.30(WEP) minutes to climb to 5000m in April '45.  This same aircraft also had sustained turn rates from 18.5-19.5 sec at 1000m.  OTOH, another serial La-7 in July '45 posted a sustained turn rate from 20.7-21.2 sec at 1000m.  So, there  (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)
Title: La7 ..how does it rate ?
Post by: leonid on February 05, 2001, 12:05:00 PM
Documents from the Scientific Test Institute, Soviet Air Force (NII VVS) tested a Bf109G-4 against a La-7.  Their conclusions were that the La-7 had an obvious advantage over the G-4 in vertical maneuverability up to 3500m.  However, it also retained equal vertical maneuverability with the G-4 up to 6500-7000m.
Title: La7 ..how does it rate ?
Post by: Vermillion on February 05, 2001, 12:31:00 PM
Nimitz, it comes down to the quality of each countries supercharger/turbosupercharger technology.

The higher you go, the better performance you need to keep up the boost in the engine. And to make a high quality supercharger/turbosupercharger you need very high quality production and machining, and you need some very high quality components, for instance bearings and high temp steel.

IMO, both the Japanese and the Soviets had a generally poor quality of supercharger technology, the Germans were moderate in this area (but the best in rocketry and jet engines), while the British and the Americans generally in the highest category. And when it comes to turbosuperchargers, the most expensive and difficult to build, I believe only the Americans deployed them in significant numbers (please correct me if I'm wrong here).

Soviet engines of the era, where very rugged reliable, and cheap to build in quantity, but used the "brute force" theory of engineering. In simple words, their engines had some of the highest displacement to horsepower ratio of any of the combatants.

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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: funked on February 05, 2001, 02:26:00 PM
Re:  Performance Variation
The M-82FN had a large difference between normal power (1470 hp) and augmented power (1850 hp).  In the Gordon & Khazanov books they mention that some of the climb tests and vertical maneuverability tests were conducted at normal power.

Re:  Power Loss at High Altitude.
The M-82FN had a single-stage blower.  The more effective engines at high altitude (Merlin, P&W R 2800) had either a turbo or a second stage that kicked in at high altitude.  A second stage is quite complicated mechanically, requires redesign of engine installation, and is going to add weight and size.  The turbo raises manufacturing issues (high temperature alloys) and the installation basically requires that you design the plane around it, like the P-38 or P-47.

With a single stage blower you can only increase the performance at altitude by driving the blower faster or putting in a bigger blower.  A bigger blower means more weight and a redesign of the engine installation with resultant packaging issues.  Driving the blower faster means you will have net power loss at lower altitudes where the power required to drive the blower faster is less than the power generated by the higher boost pressure.  The Soviets wisely chose to optimize the performance under 15,000 feet, where all the action was on the Ostfront.

[This message has been edited by funked (edited 02-05-2001).]
Title: La7 ..how does it rate ?
Post by: Seeker on February 09, 2001, 09:53:00 AM
Intersting stuff, especialy for a newbie, we don't have the LA7 in Airwarrior.

We do, however, have the La-5 and Yak.

You may like to drop by a friends site:
 http://www.btinternet.com/~fulltilt/Lavochkin.html (http://www.btinternet.com/~fulltilt/Lavochkin.html)
Title: La7 ..how does it rate ?
Post by: leonid on February 09, 2001, 01:04:00 PM
Nice site, Seeker  (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Title: La7 ..how does it rate ?
Post by: Westy on February 09, 2001, 01:57:00 PM
A very excellent web site. Thanks Seeker.

 (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)

-Westy
Title: La7 ..how does it rate ?
Post by: Fariz on February 14, 2001, 09:09:00 PM
Yes, it is a close match to yak-9u, but it shall be slightly better on verticals and slightly worse on turns. Most important is that it has better punch and more ammo than yak-9u.
Title: La7 ..how does it rate ?
Post by: RAM on February 14, 2001, 09:44:00 PM
from the link provided by seeker:


"The standard La 7 had a top speed of 592km/h at sea level - 46 km/h more than the La5fn and 72km/h faster than the Focke Wulf Fw190A-3............


The La 7 was also 15km/h faster than the Focke Wulf Fw190A-8, the latest version of this German fighter deployed on the Eastern front. With a take of weight of 3240 kg the La7 was about 1060 kgs lighter than the Fw190A-8.

Seeker, please give us the source of that information. AH's La5FN speed on the deck is greater than Fw190A8's and according to this, Fw190A8 should be 30kms/h aprox FASTER than La5FN, and only 15km/h less than La7



[This message has been edited by RAM (edited 02-14-2001).]
Title: La7 ..how does it rate ?
Post by: Sorrow[S=A] on February 15, 2001, 02:09:00 AM
IIRC RAM those last numbers would be referring to sea level speeds not the top speeds at altitude. To Soviets SL speed was much more important.
Title: La7 ..how does it rate ?
Post by: niklas on February 15, 2001, 02:14:00 AM
 
Quote

Seeker, please give us the source of that information. AH's La5FN speed on the deck is greater than Fw190A8's and according to this, Fw190A8 should be 30kms/h aprox FASTER than La5FN, and only 15km/h less than La7

A La5 with M82FNW (FNV) engine was tested in Rechlin. It had a topspeed near ground of 520km/h with emergency power.
climbperfomance with normal power 16-17m/s near sealevel.

niklas
Title: La7 ..how does it rate ?
Post by: RAM on February 15, 2001, 02:31:00 AM
 
Quote
Originally posted by Sorrow[S=A]:
IIRC RAM those last numbers would be referring to sea level speeds not the top speeds at altitude. To Soviets SL speed was much more important.


I read there that ALL those speeds listed are at sea level, Sorrow.

 
Quote
The standard La 7 had a top speed of 592km/h at sea level - 46 km/h more than the La5fn and 72km/h faster than the Focke Wulf Fw190A-3............


The La 7 was also 15km/h faster than the Focke Wulf Fw190A-8, the latest version of this German fighter deployed on the Eastern front. With a take of weight of 3240 kg the La7 was about 1060 kgs lighter than the Fw190A-8.


I read here that the SL speed of the La7 was 10mph (16km/h) faster than the Fw190A8 aprox...and I have seen lots of references that talk of Fw190A8s making 360mph on the deck. This information matches the 360mph number quite exactly.

The current Fw190A8 in AH does 350mph on the deck only...see what I mean?   (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)

[This message has been edited by RAM (edited 02-15-2001).]
Title: La7 ..how does it rate ?
Post by: RAM on February 15, 2001, 02:45:00 AM
BTW; according to the charts, La5FN does near 360mph on the deck...well, that quote says especifically that La5FN was 46km/hour SLOWER than La7 at SL, and that Fw190A8 was 15km/h Slower than La7...so 30km/hour FASTER than La5FN.

According to that page's info La5FN should be making 340Mph at SL, wich is ALMOST IDENTICAL to Fw190A5's SL speed!!!!

So I am a bit lost here, wich are the accurate numbers?...the ones in that page or the ones in the AH charts?. 20mph is quite a BIG discrepance, frankly.

And, well I dont know about La5fn, but I have read several books listing Fw190A8 speed at 360mph on the deck. Why is only 350mph in AH?.

[This message has been edited by RAM (edited 02-15-2001).]
Title: La7 ..how does it rate ?
Post by: leonid on February 15, 2001, 03:16:00 AM
RAM,
Flight data is nothing but the recorded parameters of individual aircraft, and not all aircraft are created equal.  VVS aircraft could have wide ranges of speeds sometimes for a given variant, and was usually due to production quality.  I have data of a 1945 serial La-7 that did 383mph @ SL, but you will also find data of other serial La-7s that have slower speeds, or inferior performances.  Test data of captured aircraft could be even more inaccurate, since the quality of the aircraft might be questionable.  Captured aircraft didn't usually come with an operating manual, so that left those testing the aircraft with a lot of guesswork.  Hence, maximum performance could be difficult to attain.  So, how fast was a La7?  From what I read about them they were the only VVS fighter able to catch up with a Fw190A in a dive.  In AH I know it is very difficult to catch up with a Fw190A while flying a La-5FN or Yak-9U.  At best, you will do no better than slowly creep up on a 190A, and only during an extended level run.

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leonid, Kompol
5 GIAP VVS-KA, Knights (http://www.adamfive.com/guerrero)

"Our cause is just.  The enemy will be crushed.  Victory will be ours."

[This message has been edited by leonid (edited 02-15-2001).]
Title: La7 ..how does it rate ?
Post by: niklas on February 15, 2001, 03:51:00 AM
 
Quote
Originally posted by leonid:
Test data of captured aircraft could be even more inaccurate, since the quality of the aircraft might be questionable.  Captured aircraft didn't usually come with an operating manual, so that left those testing the aircraft with a lot of guesswork.  Hence, maximum performance could be difficult to attain


Thatīs why i posted the tested climb performance. Itīs very close (normal power) to the performance claim of the VVS (the weight was a bit higher). And with normal power, max. speed was 490km/h at sealevel.

niklas
Title: La7 ..how does it rate ?
Post by: RAM on February 15, 2001, 03:58:00 AM
 
Quote
Originally posted by niklas:
Thatīs why i posted the tested climb performance. Itīs very close (normal power) to the performance claim of the VVS (the weight was a bit higher). And with normal power, max. speed was 490km/h at sealevel.

niklas


woah, that is a BIG discrepance with the AH charts and with the La5 in AH itself! 490km/h is 306mph, and without wep AH's La5 runs at 335mph! that is 30mph of discrepance!

And what about the Fw190A8, niklas? does anyone else have seen the 360mph as a SL top speed for the A8 or is only me?  (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)
Title: La7 ..how does it rate ?
Post by: leonid on February 15, 2001, 05:07:00 AM
   
Quote
Originally posted by niklas:
Thatīs why i posted the tested climb performance. Itīs very close (normal power) to the performance claim of the VVS (the weight was a bit higher). And with normal power, max. speed was 490km/h at sealevel.

niklas

Ahh, geez, niklas, never realized the La-5FN was really only as fast as a Zeke, and a slow one at that  (http://bbs.hitechcreations.com/smf/Smileys/default/tongue.gif)

[This message has been edited by leonid (edited 02-15-2001).]
Title: La7 ..how does it rate ?
Post by: niklas on February 15, 2001, 05:58:00 AM
no leonid, according to the test in Rechlin it is still 15km/h faster than a zero - with normal power!! ...wwwWRRRRUUUUUMMMmmm... a real speedking  (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif)

niklas
Title: La7 ..how does it rate ?
Post by: Vermillion on February 15, 2001, 07:17:00 AM
RAM might I suggest Soviet Combat Aircraft of the Second World War : Single-Engined Fighters
by Yefim Gordon, Dmitri Khazanov ?
 http://www.amazon.com/exec/obidos/ASIN/1857800834/qid=982243228/sr=1-2/ref=sc_b_2/107-1525636-6536510 (http://www.amazon.com/exec/obidos/ASIN/1857800834/qid=982243228/sr=1-2/ref=sc_b_2/107-1525636-6536510)

If your interested in VVS aircraft and performance, its the best single source I have seen.

One thing we should point out. If anything, the La5fn and the Yak-9U (and most likely also the La7) perform too poorly, since Pyro used the worst case performance data available.

For example, our Yak-9U has its max speed at 417mph at around 18,000 ft (which is the worse case). Another set of data availble for this aircraft states that the Yak-9U should do 437mph at 18k, which would make it easily the fastest aircraft in AH at that altitude.

If you think the Yak-9U or La5 is scary now (which many people do), it can only get worse  (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)



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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: RAM on February 15, 2001, 07:31:00 AM
 
Quote
Originally posted by Vermillion:
One thing we should point out. If anything, the La5fn and the Yak-9U (and most likely also the La7) perform too poorly, since Pyro used the worst case performance data available.

For example, our Yak-9U has its max speed at 417mph at around 18,000 ft (which is the worse case). Another set of data availble for this aircraft states that the Yak-9U should do 437mph at 18k, which would make it easily the fastest aircraft in AH at that altitude.

If you think the Yak-9U or La5 is scary now (which many people do), it can only get worse    (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)


Well, again I am talking about that link's numbers, and ,well, I dont know if niklas is joking or serious (seems that joking).

Ah, and still no word regarding the Fw190A8 making 360mph on the deck?   (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)

[This message has been edited by RAM (edited 02-15-2001).]
Title: La7 ..how does it rate ?
Post by: Vermillion on February 15, 2001, 08:32:00 AM
RAM, I will check the Pilots Handbook charts when I get home this evening that has some nice performance charts for the 190A8, too see what it says about 360mph.

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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: niklas on February 15, 2001, 11:04:00 AM
RAM, telling wrong or fantasy numbers about an aircraft wouldnīt be joking, but lying. The test was done in Rechlin, and the number exists.

Is 630km/h for a 1850hp fighter at sealevel with naca230 airfoil a joke? The number exists for the La-7 (wep, 10min rating).

In the link you find a test with 580km/h for the La-7. 50km/h more (630km/h) is equivalent to ~4-500hp. A joke?

niklas

Title: La7 ..how does it rate ?
Post by: RAM on February 15, 2001, 11:59:00 AM
 
Quote
Originally posted by niklas:
RAM, telling wrong or fantasy numbers about an aircraft wouldnīt be joking, but lying. The test was done in Rechlin, and the number exists.

Is 630km/h for a 1850hp fighter at sealevel with naca230 airfoil a joke? The number exists for the La-7 (wep, 10min rating).

In the link you find a test with 580km/h for the La-7. 50km/h more (630km/h) is equivalent to ~4-500hp. A joke?

niklas



Niklas, I know almost nil regarding soviet WWII aircraft, that is why I didnt know if you were serious or not. Simple  (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)

Verm, please let me know about what your sources say about the A8. I'd like to know about funked ,too.
Title: La7 ..how does it rate ?
Post by: Vermillion on February 15, 2001, 03:39:00 PM
Hmmm I keep getting a 404 file not found error whenver I try any link from the site other than the main page. Anyone else?

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Vermillion
**MOL**, Men of Leisure
Title: La7 ..how does it rate ?
Post by: Vermillion on February 15, 2001, 04:17:00 PM
RAM, I checked the performance charts from the english translation of the Pilots Handbook that Funked sent me.

The Handbook Charts match the Aces High Charts exactly, including the supercharger boost overide, which corresponds to AH's WEP.

I would scan them for you, but right now my scanner when "belly up" (ie it died) a couple of nights ago.

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Vermillion
**MOL**, Men of Leisure