Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: MANDOBLE on September 19, 2001, 07:47:00 AM
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This is not a whine, only a few question about the fighter that most impressed me in AH (even more than N1K2J).
Had the la7 the impressive acceleration actually present in AH while keeping even better handling than La5? this plane simply doesn't need to dive to outrun/outaccelerate anything at its level or slightly above him.
Was really a so hard to damage plane? In my experience, La7 needs even more lead than a F4U. Even when I damage its engine, it should take a lot of time until engine stops cause I've never seen one with engine killed.
Does it have any weak point below 20k?
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Hmm... I never thought that La7 is hard to damage... It is hard to catch I agree but aftrer I'm 'in range' then a 'standard' burst from my Yak-9U sends it down in flames like any other plane :)
Edit:
And not even mentioning burst from my Tyffie :D
[ 09-19-2001: Message edited by: MadBirdCZ ]
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Certainly the La7 had very good acceleration and climb at low to mid alt and was supposed to have kept other handling qualities similar to the La5. This combination made it a favourite of many of the USSR's aces including Khozedub.
I personally don't find the La7 especially tough, though it doesn't have any glass bits like the P38's tail or the 190's engine, and my usual ride right now is the La5FN with it's twin SHvaKs.
I agree with you that the La7 is more impressive than the N1K2. All other things being equal (i.e. co-e, no big angle advantage) the only thing that worries more than the La7 is the Tempest, which of course is a whopping 70 point perk.
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Matias, siento decirte que el La7 esta, a mi modo de ver, perfectamente modelado.
No lo encuentro mas duro que otros.
Su aceleracion es correcta, tengo una web rusa (museo ruso de nosedondecońo que da los datos de evaluacion de guerra, si la encuentro la posteo.
Perdona que te diga, pero con G10 en 1 vs 1 por encima de 10K el La7 es pan comido, y por debajo tiene mas posiblidades el G10 que el La7 de sobrevivir, solo es cuestion de saber cuales son sus putos debile, los tiene, y muchos, eso si, el D9 esta perdido a esa cota frente al La7.
Un saludo
Supongo
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estoooooo....... escribo un analisis que hice precisamente de un combate La7 vs 190D9, los postee en meristasion y en el foro del JG52, en el foro de meristation (simuladores) la gente opino mucho, te puede veniir bien leerlo.Hola muchachos:
"Entiendase que esto que escribo esta basado sobre combate 1 vs 1, con el la7 detras del 190D9 a unas 1.000/1.200y y por debajo de 3.000 ft. Es una situacion que se me ha dado varias veces en el AH, en otros simm's no se como sera.
Estaba hablando con un gran piloto (virtual claro) de 190D9 y me comento que el tenia dificultades para quitarse de la cola a un La7, curiosamente a mi me pasa igual, solo que yo apenas vuelo 190 (ahora estoy en ello), pero con el G10 no tengo tanta dificultad, y eso me hizo pensar.
Analicemos, (ojo, mis conjeturas pueden ser erroneas, no tengo datos aqui).
La7: El mas rapido a baja cota, muy buena capacidad de alabeo, buena capacidad de virajes en horizontal sin perdida excesiva de E, buena aceleracion, buena velocidad ascensional hasta los 10k.
FW190 D9: Mas lento que el La7, mejor capacidad de alabeo, buenos virajes en horizontal pero pierde mas E que el La7, Peor velocidad ascensional que el La7.
BF109 G10: Mas lento que el La7, peor alabeo que La7 y mucho peor que 190 D9, capacidad de viraje en horizontal limitada, sufre de perdida de E muy rapida, Excelente aceleracion, excelente velocidad ascensional, excelente control a baja velocidad.
La velocidad superior de alabeo del D9 sobre el La7 no parece capaz de decidir el resultado del combate a favor del D9 (en mi caso al menos no).
Ese alabeo mas rapido nos permite cambiar de direccion rapidamente, abortando un posible ataque desde las 6, pero la velocidad del La7 nos pone de nuevo en el punto de mira.
Unas tijeras defensivas parecen la mejor opcion, sin embargo la superior velocidad de alabeo del 190 D9 no parece suficiente frente a la aceleracion y velocidad del La7, que puede romper el conbate, alejarse 1.000/1.5000y y volver a por nosotros con mucha velocidad, tomando de nuevo la iniciativa.
Un combate en la vertical seria aun mas peligroso, pues a esa cota el La7 retiene mejor la E, sube mejor y corre mas.
No se que se debe hacer en D9 para ganar este tipo de combate. la mejor cualidad del D9 se ve mermada por la velocidad y un casi igual alabeo por parte del la7.
Quien me puede decir como hacerlo??
Contra el La7 el G10 (en mi caso al menos) tiene muchisimas mas posibilidades de salir victorioso.
La aceleracion y climb rate parece anular y aventajar la superior maniobrabilidad y velocidad del la7.
Todo consiste en un maniobrar bien en la horizontal o en tijeras hasta que el La7 pierda esa ventaja de velocidad inicial que llevaba, nivelar, acelerar, subir poco a poco, el La7 se volvera a acercar, repetiremos lo mismo, y poco a poco iremos tomando altura, hay un momento (entre los 7 y 8 k de altura) en que podremos realizar una spiral climb, viendo como poco a poco se va quedando atras el la7. Al llegar a los 10K el motor del 109 tira como un demonio, mientra el del la7 se queda atras, solo es cuestion de picar y acabar con el.
Reconozco que cuando aparecio el La7 en la MA mi nivel de supervivencia contra este avion era nula, pero ahora, despues de descubrir no ya sus puntos negativos como los positivos del g10 ese nivel a subido a un 75 o quizas 80%.
La cuestion es: Cuales son los factores mas importantes en un avion? Alabeo, velocidad, velocidad ascensional, aceleracion, maniobrabilidad horizontal, capacidad de picado, potencia de fuego?
Ya puse en un post que si tuviese que elegir 3 opciones estas serian: aceleracion, velocidad y velocidad ascensional.
La experiencia (virtual) me a enseńado que no me he equivocado, al menos con mi forma de volar.
Que 3 opciones serian las vuestras, basandose en este tipo de situaciones??"
Saludos
Supongo
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Supo, La7 vs G10:
La7 simply put the fight below 10k, G10 has no chances except to climb and forget the La. La7 outturns, outdives, outaccelerates, outclimbs, outguns and outrolls the G10 below 10k. And, in my experience, La7 is far more "strong" than any 109.
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Mira aqui:
http://www.btinternet.com/~fulltilt/Lavochkin.html (http://www.btinternet.com/~fulltilt/Lavochkin.html)
http://hep2.physics.arizona.edu/~savin/ram/indexq.html (http://hep2.physics.arizona.edu/~savin/ram/indexq.html)
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Ojo matias, que yo no digo que el G10 sea superior al La7 a menos de 10k, sino que el G10 tiene mas "armas" para salir bien de un combate que el D9 contra un La7
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no habla espaniol :(
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Tac (from a U. PC)
El LA7 no tiene tantas debilidades que puedas usar, asi que tu mejor opcion es el usar sus fortalezas en su contra.
La7 tiene una aceleracion increible, no pierde mucho E en turnos y tiene una gran ventaja en la vertical. Si lo piensas, la unica manera de joder al la7 es el meterlo en una pelea en la cual su aceleracion y poca perdida de E van a ser su perdicion.
Tijerealo. En una pelea de tijeras el la7 te va a "overshoot" con facilidad. Si el sigue derecho y no te tijerea, te da tiempo para ganar separacion e intentar otra vez. Si el se va a la vertical pa' no overshoot, clava y escapa (o gana separacion e intentalo otra vez). Si el la7 es bobo e intenta seguirte en las tijeras, has lo que puedas para coger snapshots. Muchos la7's intentan clavar y escapar cuando oyen un ping. Si no hay muchos enemigos alrededor, intenta llevar al la7 2k o menos del piso, a esa altitud el la7 sale mas perjudicado en ese tipo de peleas.
Esto funciona de maravillas en un p38, las pocas veces que he volado un 190 (d9 o a5) me sale mas dificil porque no son tan estables a bajas velocidades, pero el la7 siempre hace overshoot. el 109 es perfecto para esto, el f4 tiene gran control a baja velocidad y el g10 tiene un motor que te ayudaria a recobrar E y ganar separacion.
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Well, my Spanish is really rusty, so I only got about half what Supongo said. Anyway, I fight the LA7 quite a bit, and I hop into it on occasion, here is how I'd say the LW planes stack up against it-
109s-
109F4- You can outturn an La7 in the f4. The La7 will outroll, outdive, outclimb, and out-accelerate you though. Pretty much have to hope he gets real close to you and tries to turn fight you, or you are toast eventually.
109G2- In my opinion, this is the best matchup vs. the La7 of any of the 109s. The La7 will still outroll, outclimb, and out-accelerate you, but the difference isn't as marked as it is with the f4. The problem with flying the G2 is you are barely fast enough to get away if you run into a N1K or Spit that dives on you. The 109G2 will climb with the La7 if it is on WEP (or if not, it can stay close enough to use guns). The G2 can also outturn the La7.
109G6- In my opinion, this is the worst 109 overall, but I've heard it is a better matchup against the La7 than the G10 is. The La7 will still outroll you, outclimb you, outrun, and out-accelerate you. You'll have better luck diving with it, but it will pull away quickly as soon as you both level out. The G6 turns about the same as the LA7.
109G10- I've found the La7 vs. 109G10 to be a fairly even fight, depending on the pilot skill of both aircraft. A G10 flown to the edge can beat an La7 if it is not. If the pilot of the La7 is just as skilled, or more skilled, the 109 will generally have a tough time of it. The La7 outrolls and outruns the G10. Turning performance is similar, with the La7 having a slight edge. Below 10k, the planes will climb at close to the same rate. The La7 will outdive you, and will pull away at the bottom of a dive. That said, every time I've saddled up an la7 on the deck (in a G10), they had a damn hard time getting me off. I can think of 2 times that I've been saddled up and not gotten the kill this tour, and only one time was due to a really nice move by the La7 (the other was due to a pony sticking his nose in). However, if an La7 gets saddled up on YOU, I've found it is best to generally grab your ankles, bend over, and kiss your bellybutton goodbye, because you are going to have a REAL tough time getting him off. I've found it is best to do "mini-scissors" and skids, generally the La7 will slow down to keep you in front, then you can accelerate away for a little while. Pray that someone comes and helps remove the la7 from your butt, sometimes your prayers are answered.
190s-
190a5- Generally a poor match for an La7, in my opinion. The A5 is the best turning 190, but I don't believe it will turn with an LA7 for anything but the briefest of time. The La7 will outclimb, out-accelerate, outdive, and outrun you, as well. You can outroll the LA7, so I guess the "floppy-fish" move is a good one here? I tend to just die.
190a8- Performs even worse than the A5 does against generally everything. You can see above for how the La7 stacks up, the odds are just even more in the LA7s favor.
190d9- Almost an even match for the La7. The La7 can outturn the Dora, as well as outrun it, but the La7 only barely accelerates better and climbs a little better. Of all the 190s, you have the best chance against an La7 in this one.
Just as some additional notes that wouldn't really go anywhere else, I actually prefer the 109 to the 190 for fighting La7s. The planes seem to stack up more evenly. Also, the LA7 has no WEP above 7500 feet. It is still a very viable fighter against the Dora up until 15k or so, but above 10k the La7 will have a very hard time dealing with a 109G10 (especially if you BnZ in the G10). Hope this helps some.
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That is a very impressive comparison chart for the LA7 when compared to most other WW2 fighters in power to weight.
However I have never seen a comparison using Power/Wingloading. I guess this is a good measure of sustained turning ability. This statistic results very favorably against the Axis and allied A/C shown in the chart but not as well against American birds. Very interesting though. Would like to hear from someone on the validity of the power over wingloading comparison. Is that a Soviet test of determining what exactly?
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Man Urchin, that was precise. I agree with most of what you said, from the La7 piloting point of view. It does seem to me that the G10 gives me the most difficulty of the 109's however I kill them the most. That may be due to more of them around tho.
It seems the common mistake the 109's make is continuous loops. That's easy to follow in an La7 in lag pursuit. Heck, I don't even have my finger on the trigger. I just fly behind him until he has lost all his e, then it's easy pickin's
The 190 is the most difficult it seems and that due to the roll advantage or more accurately,due to the pilot using the roll advantage correctly.
The La7 doesn't turn that well but if you use yo-yo's, high or low, whichever the situation dictates, then the turn advantage is pretty much nulified. That roll is what gets me.
<S>
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S!
I don't fly the La-7, but obviously I run into it a lot.
It seems obvious to me that the key to successfully fighting the La-7 is to stay high unless you are in a Spitfire or N1K2.
I fly the 190D9 a lot, and at altitudes over 15,000 the La-7 is definitely inferior.
It would seem to me that the same would apply for the P51D, P47's and 109's.
The only plane which is at a definite disadvanatage to the La-7 is the Typhoon.
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S!
I don't fly the La-7, but obviously I run into it a lot.
It seems obvious to me that the key to successfully fighting the La-7 is to stay high unless you are in a Spitfire or N1K2.
I fly the 190D9 a lot, and at altitudes over 15,000 the La-7 is definitely inferior.
It would seem to me that the same would apply for the P51D, P47's and 109's.
The only plane which is at a definite disadvanatage to the La-7 is the Typhoon.
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A note about the tactics listed here:
Most La7 pilots are greens with little experience.
If you found a good pilot flying La7 there is nothing you can do to kill him except with a lot of luck or flying another La7. Even the infinite-E N1KJ2 will have tremendous problems E fighting a La.
In the specific case of D9 (my primary ride this tour), La7 outruns, outturns, outdives, outclimbs, outzooms and outaccelerates it for a wide margin at lo level. The only chance are the scissors, but D9 loose too much E with this move while La recovers the E in half a second, and, at the critical overshoot moment, D9 guns works like they used to work ... :(
Think on similar skill pilots, La7 vs anything.
Buzzbait, agree with you, these planes are superior at 15k or more. But the problem is that taking a fight from hi alt to sea level (where La7 has no par) is really easy. In the other side, fighting your way from lo level to 20k to have some advantage over the La will be a hell for sure.
[ 09-19-2001: Message edited by: MANDOBLE ]
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Supongo, about your question to win in D9 vs La7. I agree with you, D9 is the worst roller and worst turner of all 190 series and the slight rolling advantage over La will not determine any real chance to win the scissors. Your only chance is to keep in the margin of 15k and dont follow it below. Obviously, if the La7 pilot has no experience, you can win at any altitude, but always with a bit of luck.
As a matter of fact, if you are at low level and engange a La7, you will be much safer flying a 190A5 than a D9.
[ 09-19-2001: Message edited by: MANDOBLE ]
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In answer to the original post. Yes, it is correct. (the rest I don't understand since I haven't kept up on my Spanish in the past 15 years)
The La7 is simply a refinement of the La5Fn.
It has the exact same engine, while weighing slightly less, and having several aerodynamic improvements to decrease drag.
Does the La7 have any weakness below 20k?
Well, contrary to popular belief, yes. And I have flown both the La7 and the Yak-9U quite extensively since they came out.
- Speed, Climb, and Acceleration fall off quickly with altitude. In fact over 5k several aircraft are faster, at 10k quite a few planes are faster, and by 15k its quite average. But yes, if your on the deck, its quite fast, and has blinding acceleration.
- Fuel Load. The La7 has one of the smallest fuel loads in the game, and totally lacks the ability to carry drop tanks
- Visibility. With all those cockpit bars, seeing out of the La7 is quite hard. Get into rolling scissors, or multi plane engagments, and it gets hard to follow cons in this aircraft. Also visibility over the large nose (from the radial engine) makes Snapshots harder than average in AH.
- Average to Poor Ballistics. The La7 has either the ShVak or B20 cannons, which use the exact same ammunition and fire almost identically. I would rate them in capability around the same as the MG151/20, which means you have to get in close and shoot wisely. Snapshots are hard, so usually you have to have a tracking shot to be effect. Lethality is good once you hit, but hitting can be hard.
- Small Ammo Load. Combine this with the average to poor ballistics, and you have to make your shots count.
- Poor Sustained turn rates. Contrary to popular belief the La7 is a excessively poor turn fighter. It does have an excellent initial turn rate (like the F4U), but make it turn more than 90-180 degrees, and the La7 pilot is making a mistake. The La7 has a 360 degree turn time of around 21 seconds, which is roughly the same as a P51 Mustang. Any of the real turners, will eat it UP.
In short, the La7 is a quite excellent frontline air superiority fighter. Its good at low altitudes, and has a very short endurance.
I would suggest making it fight at higher altitudes, or getting it in sustained turn fights if you fly one of the TnB fighters.
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The La-7 is the fighter I fear the most by far, but as Vermillion says, it does have weaknesses.
I do find it to be extremely tough. I remember putting 10+ rounds of Hispano fire from a Tiffie into it and having absolutely no effect. None.
HiTech did mention that the La-7 has the same E retention bug as the N1K2-J, just not as bad. Both have been fixed in v1.08.
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La7, the Tempest for masses.
I met them many times. It seems that it is predominantly flown by types who can't exploit its strentghs to the fullest. I guess I never got into a decent stick flying it.
What impresses me most on La7 is its ability to do continous loops. All very tight with very short reversal on top.
Once in TA I had La7 in front of me at d4-5, both doing some 250 IAS. You know what the LA pilot did ?
He simply looped over me and dropped on my tail guns blazing.
G-10 has a chance fighting it, and it is actually a fun fight. In Dora, the way to deal is with La7 is to stay high. If they are higher, simply dive to 10k and outrun the dweeb. If they are lower, BnZ them to death. Some of the most fun kills I made in Tour 17 were against La7s, all high speed attacks with Dora ;).
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I think LA-5FN itself is more than enough for a match up against a Fw-190D-9. I'm only an average pilot, with no confidence of my skills whatsoever :D, and that was when I met a 190D-9 at low alt, he was co-alt, but looked like he had much speed(judging upon the rate of closure). I had not much choice, since he looked pretty confident for a 190D-9 at low alt, presumed he was a superior pilot than me, and all I did was just 'follow what the book says'. Keep E, don't try to chase every move, but keep behind and bug him..
And after witnessing all those blinding and brilliant 190 maneuvers, I still conquered him, and I know I couldn't have done it if I wasn't in a Lagg-5FN. The turning point was where I tricked him into following me vertical, and did me a nice hammerhead. I was not very confident of this move, since I had speed barely over 280. All I knew was that the record showed LaGG fighters out performed LW fighters under 5000ft.
And after this I said to myself..
"Man those Soviets sure made one helluva fighter"
:D
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Vermillion hit the nail on the head with his points. I still don't see why people think the La-7 is a good turner - instantaneously, yes. But after a couple of seconds it loses that ability and should pose no problems in that department.
It also has a very viscious stall - it makes sustained scissoring very tricky indeed.
Compared to the La-5FN there were quite a few changes which streamlined the shape - for instance the oil cooler was moved from under engine itself, to mid-fuselage.
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LA7 is THE plane atm in AH.
As most will know i usually fly the D9.
But when i want some fast action and fast kills, i search for a well surrounded airfield, hop into an LA7 iwht 75% fuel and there it goes.
even against multiple boogies with alt on u, u can survive impressevly long and rack up a lot of kills.
Not long ago i defended an airfield together with an exellen P47 jockey (yes he took that jug right into the air from that airfield, fighting a 5-2 from low alt and he survived, sry i forgot his name, but i was impressed).
I took an LA7, and yet within a fe seconds i headed towards the nme at 3K@350mph, there were high P51 and a ME109 and one other bird i dont remember.
I evaded the P51s attacks a couple of times, till one got greedy, he roared in, i broke, he zoomed by and went into a right turn, i followed in lag , 10 secs later BOOM 1st Pony gone.
meanwhile one other P51 attacked the P47 guy, i hit WEP, made a 0-G dive to the deck, and next time the P51 came down i zoomed up behind him BOOM 2nd stnag in pieces.
Than i had to evade the 109er and the other P51, i had spent all my ammo and landed.
Got back into the air and it went on.
Finally i think after 6-8 kills, i was killed by not less than 4 nmes, 3 behind me, that were no problem at all, and a pony comin from dead 12, i recognized to late cause i was flying with view backwards.
There is no plane in AH that impressed me more than the LA7.
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Karnak, agree with you. I also find La7 extremely tough.
And its engine is extremely durable. In three times I was lucky enough to damage a La7 engine, all the times black smoke but these La7s kept flying forever with full WEP and no performance decrease. I've flown La7 very few times and only once I got engine damage (oil), I was far from my base and decided to switch on WEP and head towards friendly territory to ditch. After several minutes with WEP on I was just over my own base and landing.
If the engine is the same than La5, La7 is a bit lighter than La5 and has some aerodynamic changes, then:
1 - Has La7 and La5 same WEP duration?
2 - Is La5 engine as though as La7 one?
3 - Does a single aerodynamic change justify a so tremendous acceleration gain? I imagine that these minor aerodynamic changes could help the La7 to outzoom/outdive a La5 and to outaccelerate a La5 at medium and hi speeds. But the acceleration from stall to 250mph should be mostly determined by the engine instead minor airframe differences. Am I wrong? It also climbs like a rocket at speeds where the drag is insignificant compared to engine power. Sincerelly, cant believe the engine sharing with La5 unless the having a big difference in weight.
4 - La7 lighter than La5 while seeming much more armoured. how could be that?
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Mandoble
To keep things straight, realize that there was a La5, a La5Fn, and the La7.
In Aces high we have the La5Fn and the La7. When you mention the La5, do actually mean the La5Fn?
Please realize that all my answers are coming from memory and I will have to check my books when I get home to be sure I'm giving you correct answers.
1 - Has La7 and La5 same WEP duration? I haven't checked it in game, but yes from my memory they should have the same WEP duration.
2 - Is La5 engine as though as La7 one? I'm not sure quite what your asking. The La5fn and the La7 have the exact same engine, with the same horsepower and the same critical altitudes
3 - Does a single aerodynamic change justify a so tremendous acceleration gain? Well, it wasn't a single change, it was quite a few. Including an overall focus on increased workmanship quality, which was a real problem with earlier VVS aircraft.
But I think you are misunderstanding how acceleration and top speed are related to one another.
Wells or Funked could probably explain it better than me, especially with the two of us speak different native languages, but it has to do with how acceleration varies with speed due the different components of drag that are involved.
Sincerelly, cant believe the engine sharing with La5 unless the having a big difference in weight. From memory I think the weight difference is between 500-700 pounds, but I'm not sure.
4 - La7 lighter than La5 while seeming much more armoured. how could be that? To be honest, I don't think the La7 is any tougher than the La5. Its just that your shot opportunities are much shorter in the La7, so it seems like its harder to kill.
However, many of the improvements in the changes from the La5 to the La7, had to do with replacing many of the wooden components with steel or aluminum. For example I think the wing spars were changed (again I would have to check).
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I love stalking and killing a La-7 in my Ki-61. Almost as fun as a Mustang or Fw kill. :)
I have had similar thoughts to Mandoble, about how La-7 can be so much better than La-5FN with the same engine.
Just because the engines are the same model, it doesn't mean they have the same power. There could have been small engineering changes, or improvements in manufacturing quality during the interval between testing of La-5FN and La-7.
Also, in addition to all the structural and aerodynamic changes to the airframe, there was a drastic change in the induction system for the engine. So while La-5FN and La-7 engines may have had the same power output on the test stand, the La-7 engine may have had significantly more power once installed in the airframe.
The bottom line for me is that the Soviet system for performance verification was quite rigorous. If their many tests said the La-7 was that much better, I believe it.
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Funkedup - the ASh-82FN engine used the La-7 was identical to that used in the La-5FN. A variant of that engine, the ASh-82FNV, was put in all later production variants of the La-7. It had the same power output, but possessed better performance at higher altitude.
Along with the many aerodynamical changes (some drastic, as already pointed out), alot of the structure was replaced with aluminium - hence the 82kg weight saving of the La-7 over the La-5FN. This all contributed to the 30 mph increase in speed at sea level compared to the La-5FN.
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Dowding, I know they both had Ash82FN. What I'm saying is that a 1944 Ash82FN might have made more power than one built in 1943, due to production variation, improvements in manufacturing, or engineering changes that did not result in a new designation.
And I'm saying that the actual power of the engine in the aircraft is affected by the induction system, and the La-7 had a much better induction system than the La-5FN.
[ 09-20-2001: Message edited by: funkedup ]
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Originally posted by funkedup:
Dowding,
And I'm saying that the actual power of the engine in the aircraft is affected by the induction system, and the La-7 had a much better induction system than the La-5FN.
[ 09-20-2001: Message edited by: funkedup ]
Rated manifold presures for the Ash82FNV were the same in both the La5FN and the La7 (yes some late La5FN's had the V varient)
I belive the cowling design on the La 7 to have greatly aided cooling............
Exhaust arrangement aided aerodynamics more than any thing else....
Whilst the air intake was more aerodynamic it became a problem in the south during the last months of the war. It picked up dust that the over nose version did not. (not a problem during the wet autumn & winter of 44 / 45)
Vermillion and dowding hit the nail on the head generally...
Also I agree that the e retention seems too high ...particularly in engine off or idle mode and even more so in manouvering..rudder and elevator surface areas are massive inproportion to the rest of the AC.
Further in a sustained dive all 109 variants (well g4 onwards at least) should pull away after a few seconds.
However below 10K the La7 had more e than a 109 in the vertical (ie in a zoom climb)
This all means that although refined from the La5FN the La7 was still basically brute force and high wing loadings etc etc
If any one can show me an authentic la5FN performance curve with its WEP band I would like to see it! (I have them (with WEP) for the La7, La5 la5F but the La5FN never shows WEP) Further I have reports stating that the WEP period was limited to 2 mins from take off in the La 5FN.
Also the La7 top speed with WEP is generally shown to be faster (below 8k)than AH by a few MPH. (however IMHO it is more important that the AC is comparable to others than hitting some spec target smack on)
However I would state that the present departure point is at too high a speed by at least 20mph IAS (level)...... I do not believe the slats are properly modelled even if someone has tried to take them into account in the snap like departure characturistic. Reccommended landing speed was 135 km/hour with full flaps (83 mph)please try this in AH.... you fall out the sky first.
Further the flaps in the La7 were controlled by a hydraulic lever. You pushed it one way to lower them and another to close them. There was no auto retract.
The rear armoured glass was far more easy to see thru than AH would have us believe. The cross profiles were thinner, made of glass and had a single wire of re enforce ment. (like the wires in the IL2m3screen) The top brace was thinner and the bottom corner braces were below the seat and certainly not obstructing view out of the AC.
The Svak 20 had longer barrels than the Mk151/20 . (120 cm v 110 cm) Thru engine version used on yaks had even a longer barrel.
Tony's "rapid fire" seems to confirm this although the B20 seems about the same. The b20 and Shvak had shorter breaches than the 151/20.
The Shvak had greater rate of fire (800 v 700 rpm) (The La 7 Shvak could be unjammed from the cockpit)
In conclusion and added to to other data re round weight, size and explosive content (which Vermillion used to have on his web site) I would venture that the Shvak 20 (99r)had better range and lethality at target then the 151/20 (82)
The 3 gun B20 was so rare on the "front" that there is an argument for perking it (except it would be then unfairly perking the 2 gun shvak version)
Tilt
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Hi Tilt,
here's some data for comparison:
The Fw 190A-8 achieved a 578 km/h top speed at sea level using 1800 HP. The Fw 190D-9 achieved 612 km/h at 1900 HP.
The Russian graphs recently posted here indicate 580 km/h for the La 5FN and 615 km/h for the La 7 (ASh-82FN). (Both at 10 min WEP setting, by the way.) Another graph even shows the La 7 (no engine variant mentioned) with 630 km/h sea level top speed.
It seems to me that the radical re-design and the more powerful engine installed in the Fw 190D-9 should be expected to yield noticably better results than the comparatively modest aerodynamic refinements the La 7 benefitted from.
Since the numbers don't reflect this, I'd speculate that a good share of the Lavochkin's performance improvement has to be due to increased engine power.
I think comparing the La 5FN and La 7 climb rates could provide the answer: The minor weight savings achieved for the La 7 should not affect the climb rate much, but a more powerful engine would be evident by noticably improved climb rates.
I've not seen Soviet test data on the La 5FN climb rates to confirm this, though.
Regards,
Henning (HoHun)
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Tilt I'm sure the m.p. ratings were the same, but even with the same m.p. limits you can get a higher full throttle altitude (and more power above full throttle altitude) if the induction inlet and ducting is more efficient.
[ 09-21-2001: Message edited by: funkedup ]
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Originally posted by HoHun:
Hi Tilt,
here's some data for comparison:
Henning (HoHun)
Ho Hun I can categorically state that they both had the same engine and that both delivered the same power at the prop (per throttle and manifold setting) upto at least 14,500ft (prior to 2nd stage of boost when the V type incurred an advantage).
We should also remember that the La 7 had a new prop that was only fitted to a very (comparatively)few La5FN's.
Re funked's point I can only say what the max power settings were at various rpm with various levels of boost. Given that the prop pitch would be set (manually in the case of the La5FN)to maximise the use of the available power then thrust is only a function of prop design....(with a little bit of exhaust thrown in)
Can you please direct me to an authentic La5FN chart that shows a WEP curve.
I confirm a bench setting of 10 mins at 2500rpm for 1850hp on the Ash82FNV. I have just never seen a VVS curve for the La5FN showing it.
Incidently on the bench rating the Ash82FNV could be run at sea level at 2600 rpm for up to 60 seconds at (i think) about 2000hp. I do not believe this was permitted in flight.
Climb rates IMHO were only marginally improved and only significantly improved under WEP, so this would agree with your theory.
Incidently it has always been my impression that a fully WEP'd D9 would out accelerate and be faster than an La7 at most altitudes above sea level. What it(the d9) could never do was out climb it(the La7)
Tilt
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The Fw 190A-8 achieved a 578 km/h top speed at sea level using 1800 HP. The Fw 190D-9 achieved 612 km/h at 1900 HP.
Not correct Hohun.
The A8 reaches 578km/h with 2000PS (1,62ata), The D-9 612 km/h with 2100PS
Tank himself reached with the D-9 583km/h near ground, when he used normal emergency power, 1750PS.
niklas
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Hi Tilt,
>Climb rates IMHO were only marginally improved and only significantly improved under WEP, so this would agree with your theory.
Thanks, that does indeed point towards unchanged engine power. Do you happen to have climb information for the La 5FN similar to the La 7 information on your website?
>Can you please direct me to an authentic La5FN chart that shows a WEP curve.
I won't judge its authenticity, but have a look at
http://www.kolumbus.fi/latesoft/tsagi_charts.html (http://www.kolumbus.fi/latesoft/tsagi_charts.html)
One of these charts shows a La 5FN (1943) with a 10 min WEP duration at low altitude.
It also shows two different La 7 versions.
>Ho Hun I can categorically state that they both had the same engine and that both delivered the same power at the prop (per throttle and manifold setting) upto at least 14,500ft (prior to 2nd stage of boost when the V type incurred an advantage).
I'd say Lavochkin did an exceptional job at streamlining the La 7 then.
My comparison to the Fw 190 was flawed since I had assumed too little power for the Fw 190A-8 - my BMW801 engine graph showed only 1800 HP WEP at sea level, but at a lower boost than quoted by Niklas.
However, I'm certain the D-9 was capable of the aforementioned 612 km/h at sea level with just 1900 HP (running with B4 fuel and Ladedrucksteigerungsrüstsatz), so that its increase in speed actually coinceded with a decrease in power. In other words, I had underestimated the Focke-Wulf's drag reduction for my comparison with that of the Lavochkin.
Regards,
Henning (HoHun)
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Wow Check how this one looks !
http://www.btinternet.com/~fulltilt/pl_02.jpg (http://www.btinternet.com/~fulltilt/pl_02.jpg)
isnt his Flag pretty ? :D
and greeeeeen colour .. ummmmmmm :cool:
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>Thanks, that does indeed point towards unchanged engine power. Do you happen to have climb information for the La 5FN similar to the La 7 information on your website?
Not as full as for the la7 with different rates under WEP etc... but one Tsagi reference at 5.1 minutes and several texts at 5.00 and 5.1 mins to 5000metres
>Can you please direct me to an authentic La5FN chart that shows a WEP curve.
>I won't judge its authenticity, but have a look at
>One of these charts shows a La 5FN (1943) with a 10 min WEP duration at low altitude.
I eat my words and it does look authentic although much later than the war years in publication. Who's is it? I want to get permission to use it?
>It also shows two different La 7 versions.
I have some problems with pic 3 on several items...What do you think of the 109K curve?
>I'd say Lavochkin did an exceptional job at streamlining the La 7 then.
The la5FN left considerable work outstanding the streamling was the work of Tsagi not Lavochkin
Did you notice the WEP less yaks?
Tilt
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Originally posted by EagleC:
Wow Check how this one looks !
Well czech this one out it was actually part of a La5FN Czech regiment fighting behind the lines in Slovakia during 44.
RENE (http://www.btinternet.com/~fulltilt/white13.jpg)
Unfortunately the la7's were only given to Czechaslovakia after the war when the Czech insignia was added.
Tilt
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"In conclusion and added to to other data re round weight, size and explosive content (which Vermillion used to have on his web site) I would venture that the Shvak 20 (99r)had better range and lethality at target then the 151/20 (82)"
If the information on this page (http://www.geocities.com/Pentagon/Base/1852/20mm.html) regarding ShVAK ammo is accurate, I would not say that the Soviet gun would be more lethal than the MG 151/20. Especially if you consider that an M-Geschoss round has about 3 times the explosive content of the ShVAK HE round.
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Hi Tilt,
>I eat my words and it does look authentic although much later than the war years in publication. Who's is it? I want to get permission to use it?
Browse back to a thread named "Tsagi Charts", there's the original URL given - with the hint that it's a bit slow, that's why I selected the other one.
>>It also shows two different La 7 versions.
>I have some problems with pic 3 on several items...What do you think of the 109K curve?
The fat black line roughly matches the Messerschmitt graphs for a Me 109K-4 with DB605D at Steig- und Kampfleistung (climb and combat power). With "dry" WEP it was about 20 km/h faster, but the speed gain with "wet" WEP (MW50 injection) would have been considerable.
According to Griehl, the Me 109K was capable of 530 km/h @ 0 m and 700 km/h @ 8000 m on dry WEP, the values increasing to 608 km/h @ 0 m and 728 km/h @ 8000 m. The Tsagi chart more or less matches these values, except having the 728 km/h at a (more logical) 6000 m altitude.
The comment "1 - 3 min only" doesn't seem to be quite correct, though, using MW50 with the DB605 was cleared for multiple 10 min bursts (and in combat often was applied continuously).
>The la5FN left considerable work outstanding the streamling was the work of Tsagi not Lavochkin
That's quite interesting! Here's some more detail on La 5 engine history:
"In 1942 most of these technical innovations [created by the MiG OKB for the radial-engined MiG-3 developement I-210/I-211] (engine cowling design and airtightness, proper positioning of the engine istself, and the I-210 wing leading edge slats) were passed on - at the order of the Narkovmavprom (state commissariat of the aircraft industry) - to the Lavochkin OKB, which adapted them successfully to the La-5, a mass-produced fighter."
(Belyakov/Marmin, "MiG - 50 Years of Secret Aircraft Design")
Regards,
Henning (HoHun)
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Originally posted by juzz:
" Especially if you consider that an M-Geschoss round has about 3 times the explosive content of the ShVAK HE round.
Ok there may be a debate about lethality at target...the Germans obviously prefered the high explosive thin shell variant to the Russians "fragmentation shell" approach and vice versa. There is a long debate on the conversion of potential chemical energy to actual damage. (Whats better a small grenade or a bigger stick of TNT?)
Whats is undeniable is the greater muzzle velocity, higher kinetic energy, higher RPM (plus better aerodynamics) of the Svak fired 99rx20. Hence I would presume that the effective active range and time to target of the Shvak munition to favour it in air combat over the 151/20.
Contrary wise I recognise that the M-geschoss 82x 20 upon exploding in certain critical internal areas would exert more damage than the 99rx20.
A neat site tho thx for finding it............ the only coment I would make is that most other texts do not agree that the b20 was reliable. It seems to have been quite unreliable in comparison to the Shvak.
Tilt
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According to the Russian Aviation Musuem (http://hep2.physics.arizona.edu/~savin/ram/index.html), this is how they went from the La-5FN to the La-7.
(http://hep2.physics.arizona.edu/~savin/ram/la-5-206_ss1169p32-prev.gif)
La-5FN "206" (http://hep2.physics.arizona.edu/~savin/ram/la-5-206.html), TsAGI modified La-5FN.
(http://hep2.physics.arizona.edu/~savin/ram/la-5fn-1944.gif)
La-5FN "Model 1944" (http://hep2.physics.arizona.edu/~savin/ram/la-5fn-1944.html), Lavochkin modified La-5FN based on TsAGI modifications but able to be mass-produced.
Then came the La-7.
[ 09-22-2001: Message edited by: juzz ]
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i saved this pic some month ago (forgot the source)
(http://members.tripod.de/luftwaffe1/sonstiges/la_var2.gif)
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En mi opinion el G10 es superior al La 7 si lo lleva un experten(SUPONGO pej). Para un piloto de nivel medio el La 7 le da mejores resultados en la relación derribos/muertes. Y lo que dice el del P-38 de las bajas velocidades, pues el mismo y su mecanismo.
Entre 5k y 15k el La 7 es un monstruo y tiene poder de fuego muy bueno a menos de 275yardas. Recordad que en AH (MA) hay pocos combates a mas de 20K.
Una escuadra de La-7 trabajando en equipo seria terrible.
A mi el avión que más me está sorprendiendo ultimamente en AH es el 205, nunca pensé que la indusrtria aeronautica italiana hubiera fabricado un avión tan peligrosillo.
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Originally posted by HoHun:
Another graph even shows the La 7 (no engine variant mentioned) with 630 km/h sea level top speed.
It´s interesting to see that the russian aviation museum website lists the La-5 "206" with 630km/h, too.
Is the La-6 "206" identical to the La-7 mentioned in some sources where they list 630km/h topspeed? It almost looks like a La-7.
niklas
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Darkglam, put another experten in the La7 and pray for the G10.
The G10 has good characteristics to flee from a La7 but not to kill it.
The La7 will set up a hi speed medium-lo level fight where the G10 has no chances to touch it. To kill effectivelly, the G10 needs to slow down the combat, else it is a flying rock, G10 is not adecuate for a high speed fight. In the other hand, planes like D9, P51, F4U (IMO, best plane against La7) or Thyph are well suited for a hi speed duel against a La7.
Darkglam, el G10 es demasiado torpe a altas velocidades como para enfrentarse a un La7, a no ser que el piloto del La7 sea un novato que sepa poco mas que hacer giritos. El G10 quizá sea el mejor avión para huir de un La7, pero no para cazarlo. Para ello necesitas un avión que tenga un excelente control a altas velocidades, como puedan ser el D9, P51, F4U o el Typh. En mi opinión, el mejor para cazar al La en un duelo a alta velocidad es el F4U (C o D).
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niklas - the '206' version was basically the La-5FN with a bunch of aerodynamic changes recommended by a Russian aeronautical institute. These changes were then transferred onto the La-7 design, which incorporated new materials not used in either the La-5FN or the '206'.
There are differences - notice the supercharger intake under the cowling of the '206' (which is actually on top of the La-5FN cowling) is gone. It was replaced by a system of intake through the wing roots - you can just about make it out on your schematic diagram.
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Dowding, my question was not whether the 206 is a La-7.
My question is whether the speed claim of 630km/h what you can read in several sources, often mentioned for a La-7, is actually from the 206 model. Or did a later "real" La-7 reach 630km/h too?
niklas
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Hi Tilt,
you mentioned a 2000 HP setting for the La-7 engine that was used (at least) in bench tests. Other data points from your website are a 596 km/h sea level speed for the 1944 La-7 and a 616 km/h top speed for the 1945 La-7.
Assuming that the later La-7 actually had the 2000 HP power setting available in flight and made 616 km/h with it, by my crude estimate it would achieve a 598 km/h sea level top speed with power reduced to 1850 HP.
This matches the 1944 La-7 quite well!
Accordingly, I'd suggest that the 1944 La-7 was limited to the 1850 HP setting, while the 1945 La-7 was cleared for the 2000 HP power setting we know from the benchmark.
The problem is that the 1945 model was faster at all altitudes - could it be that the 1944 model still employed the ASh-82FN, while the 1945 model had the ASh-82FNV with improved altitude performance?
I'm not sure I got it right yet, but I feel we're getting closer :-)
Regards,
Henning (HoHun)
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Russian performance data is supposedly an average of many a/c's performance - so the rise over time would simply be due to increased production quality, if this is true.
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Hi Juzz,
>Russian performance data is supposedly an average of many a/c's performance - so the rise over time would simply be due to increased production quality, if this is true.
In earlier years of Soviet aircraft construction, this might have been conceivable.
However, considering that the superbly streamlined and meticulously finished Focke-Wulf Fw 190-8 made less than the 1944's La-7 596 km/h sea level top speed - on more power! - , I'm afraid your suggestion that such a high level of performance could be achieved by shoddy workmanship has to be regarded as slightly unrealistic.
Regards,
Henning (HoHun)
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Hi Juzz,
>Russian performance data is supposedly an average of many a/c's performance
Let me clarify that the tests on Tilt's page
http://www.btinternet.com/~fulltilt/Perform.html (http://www.btinternet.com/~fulltilt/Perform.html)
refer to the performance of individual examples of the La-7 that are quoted with their serial number:
"During the period August 1944 La7 serial No.452101-39 underwent production test trials at the NII-VVS."
(The 1944 La-7 achieved 596 km/h at sea level.)
"During the period April 1945 La7 serial No.452132-76 underwent production test trials at the NII-VVS."
(The 1945 La-7 achieved 616 km/h at sea level.)
These values fit very well with the assumption that the 1944 La-7 had 1850 HP available in this situation, while the 1945 model could draw 2000 HP power from an improved engine.
For comparison, the Fw 190D-9 equipped with Ladedrucksteigerungsrüstsatz achieved 1900 HP at sea level while the MW50 injection later increased power output to 2140 HP.
Here's the comparison:
1944 La-7: 1850 HP - 596 km/h
1944 Fw 190D-9: 1900 HP - 612 km/h
1945 La-7: 2000 HP - 616 km/h
1945 Fw 190D-9: 2140 HP - 640 km/h
Regards,
Henning (HoHun)
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Originally posted by HoHun:
Hi Tilt,
you mentioned a 2000 HP setting for the La-7 engine that was used (at least) in bench tests. )
I was in error re the 2600 rpm time duration for the bench figures it was shown as 30 secs. (not 60)
My figure do show a gradual increase in performance over 44/45 for ex production AC.
Please also note that one set of figures is for a twin Shvak armed AC with faulty slats and the others are generally armed with 3 B20 with 130 rounds per gun.
I believe that production consistancy was quite poor. Early AC were "finished" (or not!) in the field by aircraft fiters(particularly with respect to best air mixture settings etc allowed from the cockpit adjustment etc) eg.It is known that the weight of glue/resin varied considerably (it was used as a very high strength filler when parts did not exactly fit!)
I believe all my La7 data is for the V engine.
Figures for the "206" and "etalon march 44" are often used in less thorough texts as being the capabilities of the La7.
I have always "felt" (having touched and walked around both) that (level trimmed)the La7 fuselage and engine cowl is far more drag efficient than the 190 a or even the d series.
In fact I was able to repeatedly walk between a SpitIX and the La7 at Kbely and came away thinking that what the La7 lost in housing its radial engine was more than made up for by its comparably tiny wings (which were no thicker than the Spits E wing). Plus a varnished La7 had such smooth lines compared to all the rivitted paneled AC. (Something that seeing it in the flesh again impressed)
The other thing that impressed is how small it is. Its shorter and narrower than a bf109. Only its fuselage is taller and of course its nose is broader.
Standing between the wing and tail section you are conscious of a) how close they are together and b) how massive the control surfaces were incomparison to other aircraft (I-16 apart).
Not hard data I know, but if you ever get a chance to go to Prague and see one of the only two in existance..... I do reccomend it.
Tilt
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Originally posted by HoHun:
These values fit very well with the assumption that the 1944 La-7 had 1850 HP available in this situation, while the 1945 model could draw 2000 HP power from an improved engine.
)
I dont think its an increase in engine power HoHun. The figures are given at their RPM and boost settings.
I have the test weights at home for the aircraft and will check for any other small contributing factors.
You must remember that the VVS were not as scientific in design and specification as their German contempories. Tsagi had done a brilliant job in re engineering the aerdynamics of the La 5 into the shape of the la7. That beyond this development was a series of "suck it and see" intelligent "hunches".
As you know many of tsagi's requests re engine and prop control were never implimented.
Further the La7 was the first Lavochkin to have even semi automatic throttle/ prop pitch control despite it being a so called constant speed prop.
It would not surprise me at all if there was not a whole host of settings and variables still not properly fed back to the factories by August 44 that would be required to achieve various small modifications (or establish standardised settings) to improve such things.
Tilt
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Originally posted by Tilt:
I have the test weights at home for the aircraft and will check for any other small contributing factors.[/QB]
Have checked infact the faster AC was slightly heavier.
Some interesting stuff tho. Also tested August 44 was AC (203) and another (150) was found substandard in several ways. (Both from a July batch)
203 repeated the outline figures shown on my page for -39 (but with better climb rates) 150 initially returned a max speed of 554 km/hour at ground and correspondingly less than ideal speed at higher altitudes. ( 624 @3000m & 640 @ 6000)(all without WEP)
Quote (translated)
"The same plane after governer RS-2 tuning, standard propellor mounting, improvement of fuselage and cowl sealing, improvement of external finishing"
We can only guess what the phrase "standard propellor mounting" means (translation?). the trials were then re taken at/in LII NKAP (a rear base field?)
Identically loaded the max WEP'less ground speed is given as 582 km/hour with corresponding 1st and 2nd boundry speeds as 647@3000 & 674@6000.
This is a significant improvement and equal to those figures taken in 45 against later production aircraft.
It also shows that planes were rarely tuned prior to despatch to the VVS.
Please note that the ground speed is always translated as deck speed. We cannot always assume this is as low as sea level.
I do not have WEP based figures for these tests on aircraft 150. (full designation 45210150)
Tilt
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Hi Tilt,
>Please note that the ground speed is always translated as deck speed. We cannot always assume this is as low as sea level.
The way the RAE did it was to establish the performance parameters under non-standard conditions and then standardize the measurements, and I think this must have been normal procedure everywhere. (Even at sea level, you'd have to correct the results for temperature, air pressure etc.)
>It also shows that planes were rarely tuned prior to despatch to the VVS.
For comparison, German and British procedure seems to have been that the aircraft were tested by a company test pilot in flight, tuned, and then turned over to the air force for an acceptance flight.
However, there still were occasional trouble aircraft that were either fixed by the squadrons or returned to the manufacturer for further testing.
>I believe that production consistancy was quite poor. Early AC were "finished" (or not!) in the field by aircraft fiters(particularly with respect to best air mixture settings etc allowed from the cockpit adjustment etc)
For comparison, modifications of this type were for example carried out by the USAAF Base Air Depot Area in the UK, or by the Luftwaffe's specialized "Frontschleusen", not at the actual fighting units.
>This is a significant improvement and equal to those figures taken in 45 against later production aircraft.
Good point!
>Have checked infact the faster AC was slightly heavier.
Yes, weight doesn't affect top speed much. I don't think that manual propeller control or the slats malfunctioning at low speeds had an impact on top speed either.
>I dont think its an increase in engine power HoHun. The figures are given at their RPM and boost settings.
It would be highly interesting to have a look at these!
I noticed that the 1944 La-7 was using a higher boost for top-speed flight than for climbing - could it be this was due to improper cooling at climb speed?
>The other thing that impressed is how small it is. Its shorter and narrower than a bf109. Only its fuselage is taller and of course its nose is broader.
In high-speed flight, fuselage frontal area and cooling drag are dominant, and they're significantly smaller for a liquid-cooled inline-engined aircraft.
>I have always "felt" (having touched and walked around both) that (level trimmed)the La7 fuselage and engine cowl is far more drag efficient than the 190 a or even the d series.
Much of the cooling drag is the result of internal airflow ducting, and the internal design of the BMW801 installation was outstanding, though hidden from the observer's eyes.
That the La-7 obviously had a smaller total drag shows that it was just as outstanding a design!
>I was in error re the 2600 rpm time duration for the bench figures it was shown as 30 secs. (not 60)
Looking around a bit, I've found that Eric Brown in "Testing for Combat" mentioned the La-7 to be powered by a 2000 HP engine, too. (He flew a 2-cannon version.)
Regards,
Henning (HoHun)