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Yes, the poster is also listing what appears to be TAS at higher altitude.
This tells us absolutely nothing about the relative velocity. To do that we must convert to EAS.
The effect of altitude is to increase velocity by the SMOE. An aircraft traveling a velocity of 200KEAS at sea level is traveling 200KTAS.
An aircraft traveling 200KEAS at 35,000 ft is traveling 326KTAS.
Both aircraft however are traveling at exactly the same velocity of 200KEAS and neither aircraft has any speed advantage. One just benefits from the effects of altitude.
A quick SWAG of altitude effects using the data provided in this thread shows the Bf-109K4 to be traveling at an equivalent airspeed of 299mph while the P-47N is traveling at 272mph.
440mph / 1.4678<SMOE FL24> = 299 mph EAS
467mph / 1.71295<SMOE FL325 = 272mph EAS
The Bf-109K4 is the faster of the two aircraft according to this data.
All aircraft traveling at the same angle of bank and velocity will make exactly the same turn. There is no difference in maneuverability between a P-47 traveling at 200mph KEAS and a Bf-109K4 at 200mph KEAS. At a 60 degree bank both aircraft will exactly the same turn.
Sustained maneuvering envelope will be determined by the excess power characteristics and the shape of polars.
The P47N generates a considerable amount of power at FL325. It also requires a considerable amount of power at FL325. A very quick SWAG of the Nzmax sustainable shows that at combat weight, the P47N is very close to the Bf-109K4 at 1.8ata at Take Off weight. The Bf-109K4 at 1.98ata has a substantial advantage.
In my SWAG I do convert using standard formulation from listed IAS with the types PEC.
How would you factor in roll rate at x altitude and y speed and rate of turn?
Can you walk me through the above a little more in terms of definition of terms/abreviations and how the formulas are used?
A quick SWAG of altitude effects using the data provided in this thread shows the Bf-109K4 to be traveling at an equivalent airspeed of 299mph while the P-47N is traveling at 272mph.
440mph / 1.4678<SMOE FL24> = 299 mph EAS
467mph / 1.71295<SMOE FL325 = 272mph EAS
The Bf-109K4 is the faster of the two aircraft according to this data.
so when it would be lower on the same alt as 109
Range at most economical cruise. Not a good idea in a airspace dominated by the USAAF if one wants to live to old age.
P-47D-25-RE: range ~1500 miles. Range with maximum external fuel was 1800 miles
Marshall,
Equivilent Airspeed removes the effects of altitude you understand that right? That is why engineer's use EAS to compare performance and not TAS.
Altitude effects are removed so the aircraft ARE essentially at the same altitude or at least in a comparible condition of flight.
Understand?
All the best,
Crumpp
ME109 K -- Max airspeed: 440 mph at 7500m (about 24,000 feet).
ME109H -- Max airspeed 452 mph at 19,685 feet.
ME109G8++ -- Max airspeed 426 mph at 24,280 feet
ME109G1-G6 -- Max airspeed 386 mph at 22,640 feet
P-47N -- Max airspeed 467 mph at 32,500 feet.
P-47C -- Max airspeed 433 mph at 30,000 feet.
What part of these stats do you not comprehend? As high-altitude fighter go, the P-47, even the P-47C, could beat the stuffing out of ANY variant of the ME-109 at altitudes above about 28,000 feet.
I don't think it is that hard to understand what was said.I am confused as to the point you where trying to make. Is Kurfurst somehow being deceitful for listing the range of the aircraft or are you simply pointing out that the range occurred at L/Dmax like every other airplane?
A 1000 miles might be good for a delivery flight to the EF where there was no chance of being bounced
Performance of the P-47M-1-RE included
Where did you get that mis information?
The 109K wasn`t a 'stripped down, point defense' version. It was, basically, a normal fighter like the 109G with an aerodynamically refined airframe and a later, improved high altitude engine. Actually it`s the heaviest version, but the difference is not particularly great compared to other 109G models. Like all 109s, it`s benefitted from the base concept of combining a small, light airframe with a powerful engine.
Bf-109G-6 empty weight – approx 6000 lbs (multiple sources)
Bf-109K-6 empty weight – 5161 lbs (similar to the G-10)
Somewhere between the G-6 and K, 800 lbs was lost.
Range of the Bf 109F/G/K was 1000 miles, not 350.
Wikipediastates that the Bf 109G-6 has a range, with drop tank, of 1000 km (621 miles), 528 mile without. My other sources do not support your statement either, for the F (440 miles) or G (450 miles).
It had three guns, one 30mm MK 108 and two 13mm MG 131s (the G-10/U4, G-14/U4, G-6/U4 carried the same), whereas the basic G-6, G-14, G-10 and their AS models carried the 20mm MG 151/20 cannon instead of the 30mm.
I was wrong assuming that the K had the same armament as the G-10.
I fail to see any climb advantage for the P-47N. The figures show only up to 28k feet, or 8500 meter, where it does, and 14 000 lbs weight, something like 2200 fpm, or about 11.2 m/sec. Corresponding figure for the 109K is 11.4m/sec, the same for all practical purposes. Below that altitude the climb advantage of the 109K is pronounced. OTOH, the P-47N has speed advantage in the extreme altitude regions thanks to it`s sizeable turbocharger. Up to the most common altitudes however, the 109K holds some slight speed advantage, and considerable climb rate advantage.
Actually, I got the wrong P-47 for Europe. The M was the one that the Bf 109K could have met. And while the Bf-109K would have been superior below 25k ft, the advantage would have shifted at 25k and above. For example, at 25k ft, the Bf 109K max airspeed is 444 mph, climb rate 2700 ft/min, the M's is 453 mph and 2700-3000 ft/min, at 28k ft, the K can do 441 mph and climb at 2220 ft/min, the M can co 463 mph and climb at 2700 ft/min. It gets worse at 30k ft. where the K does 438 mph and climbs at 1900 ft/min, while the M can make over 460 mph and climb at 2200 ft/min.
Basically, the two aircraft display typical qualities of a lightweight, high powered interceptor and a heavier, long range fighter with high fuel capacity. The former sports high performance and agility, high caliber weapons, the latter`s greatest virtue is it`s operational radius.
I am not an armament guy but I suspect there are those that would argue that two 50 cals and a 30 mm does not exhibit better firepower than eight 50 cals. Especially for a fighter.
Crumpp said:AFAIK the first P-47M's arrived in Europe on 04 Mar 1945 but were grounded due to engine difficulties digesting their special fuel until April 1945, just days before the war ended.
You could say the P-47M is a contemprary of the Ta-152H series and FW-190D13 series more so than the Bf-109K series. IIRC, the Bf-109K4 was operational much earlier in the war than the P47M.
No misinformation is posted. As I understand the documentation, they arrived at the group for operational testing then but were not posted to operational status until 04 Mar 45. Only half the squadron aborted with mechanical difficulties on their first mission in January. The other half flew the mission for the operational trials. Assesments were still needed of types usefulness in combat.
If you want to say that the type was operational from Jan 45 you are free to do so. IMHO, it would be like claiming the FW-190D9 was operational in October 1944. That would not be true however as the type was undergoing operational trials, the last phase of the testing regime to asses its worth as a combat aircraft before acceptance by the gaining service.
The type maintained this dismal relability rate throughout the trials until Pratt and Whitney got involved. Unfortunately Pratt and Whitney's solution turn out not to be the answer and it appears the type was prematurely posted to operational status.
The 50% abort rate the operational trials averaged was never fixed so that when on the very first mission in operational status, it led to the type being grounded until April 1945 so that relability could be increased to an acceptable level for a USAAF Operational Squadron.
Once again, the P47M was not a contemporary of the Bf-109K but belongs alongside the Ta-152H series, FW-190D13 series, and other late war aircraft that were not developed designs by wars end.
That is my opinion. You are entitled to paint the aircraft as fully developed and a viable operational aircraft if you like.
I disagree with these comments. The first delivery of the Bf 109k was in October, 1944. The first delivery of the P-47N was September, 1944, one month earlier. I could not get a delivery start date for the P-47, but considering that in December, 1944, 130 P-47M were delivered and only 24 "N"s, it is reasonable to assume that delivery of the first P-47Ms was in the September, or before, time frame. This does not justify the statement that the P-47M or N was not a contemporary of the Bf-109K. Maintenance problems appear to be minor from a mechanical standpoints (there were some deaths) since the initial problems occurred in March and the P-47Ms were operational in April. I am sure that the reason that the P-47M was not introduce until early '45, was because the Allies were not as hard pressed to introduce new technology as were the Germans. I am sure that the Bf 109K did not go through as rigorous testing as Allied aircraft nor did the pilots go through as intensive checkout as the Allied pilots. It probably took the US four to six months to get a new aircraft, once delivered into the fighting squadron, how long do you think it took the Germans to fly the first operational mission after the Bf 109K was delivered? Probably days. I am also sure that had the Allies been threatened in early to mid '44 by the Luftwaffe retaking control of the skies over Germany, you would have seen the P-47M and N, and probably P-51H fully operational in the fall of '44. As it were, they had the highly capable P-51B/Ds and P-47D-25s that, in the quantities available, easily handled the Luftwaffe and any of the advance aircraft, including jets, they could throw up. There was just not a lot of pressure on the Allies to field advanced technology aircraft, except in Pacific, where Kamikazes were a real threat to the fleet.
I disagree with these comments. The first delivery of the Bf 109k was in October, 1944. The first delivery of the P-47N was September, 1944, one month earlier. I could not get a delivery start date for the P-47, but considering that in December, 1944, 130 P-47M were delivered and only 24 "N"s, it is reasonable to assume that delivery of the first P-47Ms was in the September, or before, time frame. This does not justify the statement that the P-47M or N was not a contemporary of the Bf-109K.
The performance of the YP-47M was excellent, with a top speed of 761 KPH (473 MPH), and the variant was rushed into production to counter the threat of the new German V-1 cruise missiles and German jet fighters. 130 P-47Ms were built, with the first arriving in Europe in early 1945. However, the type suffered persistent teething problems in the field and did not see much action until the war was all but over.
What is the importance of roll rate or how do I calculate it?
SWAG - Scientific Wild Azz Guess
All the best,
Crumpp
The effect of altitude is to increase velocity by the SMOE. An aircraft traveling a velocity of 200KEAS at sea level is traveling 200KTAS.
An aircraft traveling 200KEAS at 35,000 ft is traveling 326KTAS.
Both aircraft however are traveling at exactly the same velocity of 200KEAS and neither aircraft has any speed advantage. One just benefits from the effects of altitude.
A quick SWAG of altitude effects using the data provided in this thread shows the Bf-109K4 to be traveling at an equivalent airspeed of 299mph while the P-47N is traveling at 272mph.
440mph / 1.4678<SMOE FL24> = 299 mph EAS
467mph / 1.71295<SMOE FL325 = 272mph EAS
The Bf-109K4 is the faster of the two aircraft according to this data.
SMOE - Standard means of evaluation - Term used to descibe 1/SQRT sigma. Sigma is the density ratio which equals pressure/pressure at sea level on a standard day. Pressure units are in slugs/ft^3
To convert velocity in EAS to TAS we have to account for density effects of the atmosphere.
Here is a primer on airspeed:
Airspeed - Wikipedia, the free encyclopedia
All the best,
Crumpp