Time to Climb Records.
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Time to climb records reply.
From what I have seen, the new rate of climb 'records' might be somewhat misleading, such as an initial rate of climb record for the MiG-29 being over 300m/s, but average rate to 6000 m is only 109. The Su 27 that someone mentioned with a 45,000 ft/sec claim (slower than the 65,000 for the MiG-29) is based only on math, from what I know, therefore, is 'illusory'.
The real record might still be held by the F-15, at 30,000 feet in one minute. One of the two engines of the 15 has more thrust than both Su-27's.
The 5th generation jets are slower, so unless an unbelievable new type of engine was put into a F-22, might not be so good, but, you never know, I guess. F-22's stated 1,200 mph top speed is not very threatening to the F-15's capability to go supersonic in a vertical climb.
The real record might still be held by the F-15, at 30,000 feet in one minute. One of the two engines of the 15 has more thrust than both Su-27's.
The 5th generation jets are slower, so unless an unbelievable new type of engine was put into a F-22, might not be so good, but, you never know, I guess. F-22's stated 1,200 mph top speed is not very threatening to the F-15's capability to go supersonic in a vertical climb.
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I don't have the full answer, but the time to height records in fast jets are not achieved using "Saturn V" like profiles. The aeroplane is climbed very steeply initially at an air speed, and then with an increasing nose attitude to sustain a mach number... at some pre-calculated point, the attitude is allowed to come back down again to allow further acceleration before re-entering the steep climb. This would be achieved, I think, with generous use of zero g and possibly a shallow descent (?)
An expert can chip in here whenever they want, but I think the process happens twice on the way up with the final zoom being near vertical. During that last zoom, the engines run out of air and flame out, and the aircraft is definitely ballistic as it goes over the top prior to gravity doing its thing...
There is nothing quite like pulling to the vertical in a powerful fast jet...
An expert can chip in here whenever they want, but I think the process happens twice on the way up with the final zoom being near vertical. During that last zoom, the engines run out of air and flame out, and the aircraft is definitely ballistic as it goes over the top prior to gravity doing its thing...
There is nothing quite like pulling to the vertical in a powerful fast jet...
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Time to climb records
With regard to the F-15 Streak Eagle climb records, a chapter in the book 'Air Superiority Blue - The F-15 Story' has a few facts about the record attempts.
The book details the F-15 program as written by the design and engineering team. Quite a good read.
The engines were spec P&W F100 engines, although the engineers made careful adjustments that increased allowable ITT by 50 deg F. This added about 3% to the engines thrust, though it didn't exceed the metallurgical limits of any of the components. After the eight records were set, both engines were inspected and returned to the wider fleet.
Grand Forks Nth Dakota in January was chosen as the location for the attempts.."to pick a place where the air was as dense as possible for as much of the flightpath as possible".
Any hardware that could be safely removed and still maintain the CoG limits was taken out.(incl. flap actuators & gun)
The eight records set were (from a standing start):
3000m/9842ft - 27.6sec
6000m/19,685ft - 39.3sec
9000m/26,527ft - 48.9sec
12000m/39,370ft - 59.4sec
15000m/49,212ft - 77.05sec
20000m/65,617ft - 122.95sec
25000m/82,021ft - 160.95sec
30000m/98,425ft - 207.6sec
The 6000, 9000 and 12000m records were set on the same flight. All records up to 12000m were set by accellerating level to 485KIAS after lift-off, then 5g rotate to 80 deg nose up. The aircraft was supersonic through about 6000'.
The higher records were set using unique profiles designed for each attempt, but each involved a similar climb entry using 2.5g immelman from 485KIAS after liftoff, then level(ish) accelleration at about 32000' before entering climb so-mewhere above M2.0 at about 60 deg nose up.
Take off run was about 400ft (seven aircraft lengths).
The book goes into a bewildering amount of high end detail about the lead up training & testing by the aero vort types and the test pilots to find the best profiles to fly for each record.
Really good thread by the way. Should be more of it.
The book details the F-15 program as written by the design and engineering team. Quite a good read.
The engines were spec P&W F100 engines, although the engineers made careful adjustments that increased allowable ITT by 50 deg F. This added about 3% to the engines thrust, though it didn't exceed the metallurgical limits of any of the components. After the eight records were set, both engines were inspected and returned to the wider fleet.
Grand Forks Nth Dakota in January was chosen as the location for the attempts.."to pick a place where the air was as dense as possible for as much of the flightpath as possible".
Any hardware that could be safely removed and still maintain the CoG limits was taken out.(incl. flap actuators & gun)
The eight records set were (from a standing start):
3000m/9842ft - 27.6sec
6000m/19,685ft - 39.3sec
9000m/26,527ft - 48.9sec
12000m/39,370ft - 59.4sec
15000m/49,212ft - 77.05sec
20000m/65,617ft - 122.95sec
25000m/82,021ft - 160.95sec
30000m/98,425ft - 207.6sec
The 6000, 9000 and 12000m records were set on the same flight. All records up to 12000m were set by accellerating level to 485KIAS after lift-off, then 5g rotate to 80 deg nose up. The aircraft was supersonic through about 6000'.
The higher records were set using unique profiles designed for each attempt, but each involved a similar climb entry using 2.5g immelman from 485KIAS after liftoff, then level(ish) accelleration at about 32000' before entering climb so-mewhere above M2.0 at about 60 deg nose up.
Take off run was about 400ft (seven aircraft lengths).
The book goes into a bewildering amount of high end detail about the lead up training & testing by the aero vort types and the test pilots to find the best profiles to fly for each record.
Really good thread by the way. Should be more of it.
Last edited by Love Monkey; 4th Feb 2012 at 21:32.
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More on rate of climb record.
Some terrific relplies here, thanks. Terrific discussion.
In reference to the F-22 concept by someone, unexpectedly, the F-22 is considerably heavier than the F-15, so, alhtough my ealier reference to the F-22 having a top speed of only 1200 mph, which turns out to be its' supercruise speed, with top speed of a stated 1600mph at altitude, that still is not particularly comperable to an F-15.
The more hopped up engines concept for maybe that the F-22 would be a good one to try for new records with, maybe is looking more like should be done to an F-15.
Note: in case this one would count, maybe a rocket boosted new, fast Mirage would have a really, really hard sustained rate of climb. That one is not a conventional jet setup, so I don't know if it counts.
Mirage has used rocket boosting for about 40 years....
In reference to the F-22 concept by someone, unexpectedly, the F-22 is considerably heavier than the F-15, so, alhtough my ealier reference to the F-22 having a top speed of only 1200 mph, which turns out to be its' supercruise speed, with top speed of a stated 1600mph at altitude, that still is not particularly comperable to an F-15.
The more hopped up engines concept for maybe that the F-22 would be a good one to try for new records with, maybe is looking more like should be done to an F-15.
Note: in case this one would count, maybe a rocket boosted new, fast Mirage would have a really, really hard sustained rate of climb. That one is not a conventional jet setup, so I don't know if it counts.
Mirage has used rocket boosting for about 40 years....
Mirage?? Pah!! I challenged a Mirage pilot to a race to 1000' - I was in a Huey - and he would not take me on.
Mind you, it was from a standing start outside a shut-down aircraft.
Mind you, it was from a standing start outside a shut-down aircraft.
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