CORSNING
Tech Sergeant
A lot of people aren't aware of the fact that a P-39 had the same sustained turn rate of a P-40........TRUE STORY.
Best fighter in Eastern Front, 1943.
- Thread starter Tante Ju
- Start date
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starling
Airman 1st Class
Yak9 for me.built in huge numbers:from 42 onwards,good armament,cheers.
parsifal
Colonel
good to see ya starling. Havent seen you for a while now.....
CORSNING
Tech Sergeant
Hi starling. The Yak-9 was the most overall maneuverable aircraft on the pole in the horizontal plane. Its roll rate was close enough to Fw-190 to allow its it to use its superior turn and vertical abilities to full effect. 1,260hp in a 6,320 lbs. aircraft. 323mph/S.L. 372mph/13,760ft. 5,000m/5.1min. It had the performance needed at low/medium levels. In 1943 it was dynamic (quick acceleration/deceleration).
Chuck Yeager said @ 100ft, nothing could touch the P-39!
No it wont' happen
A difference of opinions should always be an enrichment, not an annoyance, but olny with people that have something to say.
That excludes DonL -Bada: it would be difficult to them to demonstrate to an educated engeneer how a plane of 4070 (4270)/ 18.3 = 222 kg/m² WL and 4070/1700 2.39 kg/hp Power Loading could deal (on a dogfight) with another of 3290/17.6 = 187 kg/m² WL and only 3290/1850 = 1.78 kg/hp PL!!!
Just to say it's a huge difference, in the world of aeronautics.
About diving: at least at first moments the La-5 FN should be better due to the higher acceleration (because of the old well known Newton law F = m "gamma", cf P.L.), then FW and only after, taking the advantage because of the bigger weight and (mightbe) sturdier stucture.
About roll, the La-5 had big ailerons (1.32 or... 1.62 m² depending on sources) proportionaly to it's wing aera, and shorter wingspan (9.8 vs 10.5). So good roll rate.
Better than FW-190's? I can't be sure, but surely better radial acceleration and command respunse due to lower inertia moments on it's tapered wing (all loads being concentrated on the wing root). This couldn' be said to a FW-190 carriying weapons on a lot of plane's parts (wing size) far away (all is relative...) from it's GC.
Anyway compare 747's roll rate and Pitt's or CAP -232 one's.
I'm not pro- or anti- someting or something esle
, j'm just saying that comparing planes it's not a matter of taste (i like lemon, not choklate), but physics...Regards
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CORSNING
Tech Sergeant
Hi Altea,
At least half of the info I have posted about VVS aircraft is from Erik Pilawskii'S book mentioned in post 105. The La-5 and Yak-9
At least half of the info I have posted about VVS aircraft is from Erik Pilawskii'S book mentioned in post 105. The La-5 and Yak-9
CORSNING
Tech Sergeant
Woops!, slight of hand. Sorry guys.
Hi Altea,
I'll pick up where I stumbled from. The La-5FN and Yak-9 were very close in roll rates. Neither was quite up the Fw-190 standards under 325mph. Both of their successors were though, La-7 and Yak-3. I am not sure how close the P-39N came to the -5FN or -9. Removing the wing guns of the 39 did increase its roll rate but I have not found a graph yet that says how much.
Hi Altea,
I'll pick up where I stumbled from. The La-5FN and Yak-9 were very close in roll rates. Neither was quite up the Fw-190 standards under 325mph. Both of their successors were though, La-7 and Yak-3. I am not sure how close the P-39N came to the -5FN or -9. Removing the wing guns of the 39 did increase its roll rate but I have not found a graph yet that says how much.
claidemore
Senior Airman
Yup, totally agree Altea. Of course as soon as you post some numbers to prove the physics, the "plane of their choice"-ophile will challenge it and ask for sources, discredit the source (usually with a claim of bias or propaganda basis), provide another source, prove you're wrong with an anecdote, or just flat out tell you that you are wrong!
Not always the most educational discussions, but certainly entertaining!
Not always the most educational discussions, but certainly entertaining!
Hello?
I didn't understand. From where?Woops!, slight of hand. Sorry guys.
Hi Altea,
I'll pick up where I stumbled from.
What does it mean "close"?
Can you provide graphs or valuable data?
Why should it be? The established roll rate is undependent of that.
I do not say for radial acceleration, ant time respunse, that should be really improved.
Regards
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Yup, totally agree Altea. Of course as soon as you post some numbers to prove the physics, the "plane of their choice"-ophile will challenge it and ask for sources, discredit the source (usually with a claim of bias or propaganda basis), provide another source, prove you're wrong with an anecdote, or just flat out tell you that you are wrong!
Not always the most educational discussions, but certainly entertaining!
Discredit my source? Maybe soviet communist propaganda inflated La5-FN power, reduced real size and weight?
Unfortunately to them there are some Shvetsov M-82 flying till now, and La-7, Yak-3 etc. in museums.
And what about Marcel Albert, the american capitalistic buisinessmen, opinion about Yak-1/3/9 vs FW-190A (and tests, he flew both of them as the 109 afterwar). And so for the royalist (even anti-republican) nobleman Marquis de la Poype.
Biaised by soviet propaganda too, as Tchekh La-5FN pilots, that hate soviet system
?Anyway; let's see
parsifal
Colonel
Theres nothing wrong with cross examination of the evidence, its just when its so one eyed, and takes the form of personal attack that I object
From soviet tests, sure. The D-2 tested in april 1942 performed the full serial sustainted turn in only 17.7 - 18,7 secunds at 1 km height. An astonishing result!
Unfortunatly we're lacking some more precision about test conditions, weight and power used...
The P-40C turned in 18s in october 41, the P-40E in 19.2s in july 42.
Both were hugely beatten the soviet FW-190A-5 that performed it in full 22-23s.
Regards
It seems anyway that due to a lower WL, the P-40 made turns in shorter radius and... of course at lower speed.
Regards
CORSNING
Tech Sergeant
Altea,
I have degenerative arthritis in the spine of my neck. That coupled with gout causes my hands to lock up when I'm typing sometimes. When I hit the wrong letter key, I can correct it. When I hit the wrong Enter key....well, you get my post #127. Sorry.
La-5 and Yak-9 close in roll to Fw-190? I have no exact graph (wish I did), but the graph at wwiiaircraftperformance.org show that the 190 begins to be eclipsed by other aircraft starting around 325mph. Close is in my post #124. No graph, just from what I have read in Erik's book and Conversation with N. Glodnikov.
I consider these two to be "valuable data". I would agree with anyone that having an actual military graph or document is a more accuate measure.
I truly love seeing accurate documents, even when they prove my opinion is wrong. That's just the way to learn when your not an earonautical engineer.
I have degenerative arthritis in the spine of my neck. That coupled with gout causes my hands to lock up when I'm typing sometimes. When I hit the wrong letter key, I can correct it. When I hit the wrong Enter key....well, you get my post #127. Sorry.
La-5 and Yak-9 close in roll to Fw-190? I have no exact graph (wish I did), but the graph at wwiiaircraftperformance.org show that the 190 begins to be eclipsed by other aircraft starting around 325mph. Close is in my post #124. No graph, just from what I have read in Erik's book and Conversation with N. Glodnikov.
I consider these two to be "valuable data". I would agree with anyone that having an actual military graph or document is a more accuate measure.
I truly love seeing accurate documents, even when they prove my opinion is wrong. That's just the way to learn when your not an earonautical engineer.
CORSNING
Tech Sergeant
I have read a few places that wing guns and other equipment was removed from the P-39. One of the benifits listed is a better roll rate...??? As I said, I am not an aeronautical engineer. Sooooo, is this correct or not? I'm asking because I don't know personally.
Shortround6
Major General
I am not an aeronautical engineer either but I think we may be getting confused between roll rate and roll acceleration. Roll rate being the maximum number of degrees per second that the plane would roll at a given speed and roll acceleration being how fast it reaches that roll rate. And perhaps how fast it can stop rolling? Most planes in combat are not going to perform consecutive barrel rolls but how fast they can go from level flight to a 60 degree or better bank to do a hard turn is important. Or go from a steep left bank to a steep right bank. A plane with quick roll acceleration (response) but a slightly lower peak roll rate may have an advantage over a plane with a higher roll rate that takes a bit longer to reach it's peak roll rate. Pulling guns and weight from the wings should reduce the inertia and increase the roll acceleration even of it does not change the ultimate roll rate.
CORSNING
Tech Sergeant
Thank you Shortround6. That all makes sense to me.
Altea,
As I said, the roll acceleration (thanks again Shortround) in the -5FN and Yak-9 was close enough to allow them to use their other maneuvers to full advantage against the Fw-190.
Altea,
As I said, the roll acceleration (thanks again Shortround) in the -5FN and Yak-9 was close enough to allow them to use their other maneuvers to full advantage against the Fw-190.
Hello,
I didn't knew that Pilawky pretends himself as an expert in mechanics of flight
Yak-9 and La-5 are not exactly the same plane, aileron's size is bigger proportionaly to the wing size on the La-5. It's wing span is smaller.
http://mig3.sovietwarplanes.com/lagg3/structure/structure.htm
About the roll acceleration i have little doubts that La-5 was better due to momentum effects. The CG of its wing located closer to the root, and a lot of aileron aera on the wing tips. So the La-5's wing with no doubt is opposing lower resistance to aileron's work for roll start, or roll stop.
About the peak roll, there should be a discussion.
1) the FW had bigger ailerons to wing size ratio.
2) In the La-5 they were larger to wing chord, and better located.
3) La-5 wings were shorter: 9,79 to 10.51 m.
Reducing Yak-55 wing span from 9 to 8.1m (-10%), increases the roll rate from 240°/s to 360°/s (+ 50%)! This seems to be a major factor.
Regards
PS, thanks to shortround
I feel sorry for you...
Golodnikov's OK!
I didn't knew that Pilawky pretends himself as an expert in mechanics of flight
Yak-9 and La-5 are not exactly the same plane, aileron's size is bigger proportionaly to the wing size on the La-5. It's wing span is smaller.
http://mig3.sovietwarplanes.com/lagg3/structure/structure.htm
About the roll acceleration i have little doubts that La-5 was better due to momentum effects. The CG of its wing located closer to the root, and a lot of aileron aera on the wing tips. So the La-5's wing with no doubt is opposing lower resistance to aileron's work for roll start, or roll stop.
About the peak roll, there should be a discussion.
1) the FW had bigger ailerons to wing size ratio.
2) In the La-5 they were larger to wing chord, and better located.
3) La-5 wings were shorter: 9,79 to 10.51 m.
Reducing Yak-55 wing span from 9 to 8.1m (-10%), increases the roll rate from 240°/s to 360°/s (+ 50%)! This seems to be a major factor.
Regards
PS, thanks to shortround
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CORSNING
Tech Sergeant
Altea, don't you or anyone else ever feel sorry for me.. I met a woman twelve years ago that put more into my life than 95% of the people who ever lived will ever have. I have a very simple thing. She had it too but hers was operable mine wasn't. As long as I have her and great teachers on this sight, I'm good to go.:8)
. I met a woman twelve years ago that put more into my life than 95% of the people who ever lived will ever have. I have a very simple thing. She had it too but hers was operable mine wasn't. As long as I have her and great teachers on this sight, I'm good to go.:8)CORSNING
Tech Sergeant
I almost forgot. Shortround has given me some static, but it was well deserved. You both seem like some pretty cool dudes with some real knowledge to share. I'm going to enjoy reading both your posts in the future. Thanks to both you guys.
