Forum: General F-22A Raptor forum

toan wrote:

According to AW&ST, June 12, 2006:

For the anti-cruise missile mission, F-22A can cruise 41 minutes with the speed of around 1.5 Mach, while the traditional fighters like F-15 and F-16 can just cruise 7 minutes with that speed.

Exactly my point. Thank you.

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toan wrote:

According to AW&ST, June 12, 2006:

For the anti-cruise missile mission, F-22A can cruise 41 minutes with the speed of around 1.5 Mach, while the traditional fighters like F-15 and F-16 can just cruise 7 minutes with that speed.

1. According to the previous report, Raptor could make 1.5 Mach supercruise with 80% military thrust at medium to high altitude.

2. Mach 1 is about 295 m/sec at the height of 30,000~40,000fts. Therefore, cruising 41 minutes with the speed of around 1.5 Mach should roughly equal to the distance of 295/1000*3600*1.5*41/60 = 1,089 km / 677 miles / 588 nms.

3. Suppose that around 80% of the internal fuel of Rapator is used for this cruise (20,650 Ib * 0.8 = 16,520 Ib), then the SR for F-22 in this condition should be around 0.0356 nm/lb.

677 miles was basically the same exact figure I calculated, 670 miles. If the F-15 can only travel for 7 minutes at that speed, and the Raptor for 40+, that makes the Raptor about 6 times more fuel/speed efficient. Three reasons: lower drag, more fuel efficient engines, greater fuel load. This is all pretty elemental.

toan wrote:

According to AW&ST, June 12, 2006:

For the anti-cruise missile mission, F-22A can cruise 41 minutes with the speed of around 1.5 Mach, while the traditional fighters like F-15 and F-16 can just cruise 7 minutes with that speed.

1. According to the previous report, Raptor could make 1.5 Mach supercruise with 80% military thrust at medium to high altitude.

2. Mach 1 is about 295 m/sec at the height of 30,000~40,000fts. Therefore, cruising 41 minutes with the speed of around 1.5 Mach should roughly equal to the distance of 295/1000*3600*1.5*41/60 = 1,089 km / 677 miles / 588 nms.

3. Suppose that around 80% of the internal fuel of Rapator is used for this cruise (20,650 Ib * 0.8 = 16,520 Ib), then the SR for F-22 in this condition should be around 0.0356 nm/lb.

As for F-15C:

1. Mach 1 is about 295 m/sec at the height of 30,000~40,000fts. Therefore, cruising 7 minutes with the speed of around 1.5 Mach should roughly equal to the distance of 295/1000*3600*1.5*7/60 = 186 km / 116 miles / 100 nms.

2. Suppose that around 80% of the internal fuel of F-15C is used for this cruise (6,103 kg * 2.2025 * 0.8 = 10,753 Ib), then the SR for F-15C in this condition should be around 0.0093 nm/lb

As for Eurofighter:

http://www.airpower.at/flugzeuge/eurofighter/faq.htm

Gebiete die von Graz oder Zeltweg weiter entfernt sind - z.b. der Nordosten Österreichs mit der Bundeshauptstadt oder der exponierte Westen mit dem engen Lufträumen Tirol und Vorarlberg - können mit dem Eurofighter Typhoon in rund der Hälfte der Zeit erreicht werden. Und nicht nur das. Einmal angekommen kann der Eurofighter Typhoon auch wesentlich länger im Luftraum verbleiben. Während ein Draken mangels Treibstoff nur wenige Minuten über Vorarlberg verbringen kann, ist der Eurofighter Typhoon selbst ohne Außentanks in der Lage dort eine Stunde zu kreisen.

From Graz or tent way further is distant - e.g. the northeast of Austria with the Federal Capital or the exposed west with close air spaces the Tirol and Vorarlberg - can with the Eurofighter Typhoon in approximately half of the time orders be achieved. And not only that. Once arrived the Eurofighter Typhoon can remain also substantially longer in the air space. While a Draken can spend few minutes over Vorarlberg for lack of fuel only, is to be circled the Eurofighter Typhoon without external tanks in a the position there one hour

A:
1. The distance from Graz to the northeast of Austria is about 142~175 km, so "EF-2000 can get there in five minutes" means the average speed of EF-2000 for the mission is about 1.6~2.0 Mach.

2. The distance from Graz to Vorarlberg is about 430 km, which means that EF-2000 shall be able to fly to the area 400~450 km away from the base, loitering there for about 1 hour and then back to the base with internal fuel only.

And this means...?

I certainly hope that the AF is maintaining its record of understating the Raptor's capabilities.

Sorry to awaken a sleeping topic, but the following question has been nagging me for some time. The air force states that the F-22, with proper tanking, can achieve a long combat radius. But is combat radius by definition a measure of innate, unrefueled range? Thus, I cannot quite make sense of that statement. Do I grasp the term correctly?

JCSVT wrote:

I think this has been posted here before.

Based on ~35,100lbs of gas (full internal, two CFTs, and 3 610 gallon tanks) the F-15C has a ferry range of 3,100nm according to the USAF officially. That translates to a SR of roughly 0.088 nm/lb. I assume thats at a nominal cruise mach of about 0.80 or so. The SR for the F-22 according to Stevenson's slide is ~0.076 nm/lb at M0.9 at 40,000'. There is one data point on his graph for M0.8 at 30Kft which is about 0.005 nm/lb better than the 0.90/30Kft. Assuming that holds true for 40Kft that translates to 0.080 nm/lb. Thus with the normal load out for the F-22 and F-15C we have the following max ranges (still air, run 'em dry)

F-15C

1,549nm

F-22 (20,650lbs/18,400lbs)

M 0.80 @ 40 Kft (estimated)- 1,652/1472nm

M 0.90 @ 40 Kft - 1,569/1,398nm

M 1.00 @ 50 Kft - 1,239/1,104nm

M 1.5 @ 45 Kft - 826/736nm

M 1.5 @ 50 Kft (estimated) - 939/836nm

May I request the source?

There is some good estimation going on here, and it has been stated correctly that thrust isn't free. The only problem I see is that all these elaborate calculations assume the two engines are burning the same fuel, which they don't, from what I've read.

Granted, I've been away from the fighter community for almost four years now....but, current air force regulations require a "space suit", for lack of a better description, for flights above 50,000 feet. That being said, I have my doubts that the F-22 cruises at 60K. Yes, I'm sure it can reach that altitude, but my money is on most operations being conducted at between 30K and 40K.

VPRGUY wrote:

Granted, I've been away from the fighter community for almost four years now....but, current air force regulations require a "space suit", for lack of a better description, for flights above 50,000 feet. That being said, I have my doubts that the F-22 cruises at 60K. Yes, I'm sure it can reach that altitude, but my money is on most operations being conducted at between 30K and 40K.

It routinely operates at altitudes above that of most fighters. F-22 pilots wear a different flight suit than the ones used by teen series fighters. It's designed for both higher altitudes, higher airspeeds, and higher G forces.

There was a female F-22 test pilot who spoke during an interview for one of the several programs on the Military Channel did on the F-22. She stated that she was thrilled that she was flying at 60K-ft., 800kts while pulling 5G's! She stated that no other fighter could do this. She was getting excited simply talking what she had recently done.
The F-22A was initially cleared to operate at 60,000-ft. I think it was 2007 when it was cleared to operate at 65,000-ft.!

F-22 Raptor is an evolution in Modern 5th generation Fighter Aircraft developed by the United States, but its a pity that only 170odd will be in service, numbers should have gone up considerably, as its more mantainable than the f-35 JSF, and is way better in many areas. for me the f-35 is a publicity stunt, and just a showcase of what technology can bring to modern aireal warfare. it wont see full induction/service as predicted. need of the hour is to increase production for the f-22, f-15's latest version which has some stealth capabilities. retire old f-16s and procure new more advanced f-16s with aesa radars etc etc

@pakviper:
I doubt the F-35 is going to be more expensive to maintain, considering maintenance was a primary design goal, and the F-22 is simply a larger 2-engined aircraft with more extensive stealth coatings. The F-35 provides a huge leap over even a very advanced block F-16.

pakviper wrote:

for me the f-35 is a publicity stunt, and just a showcase of what technology can bring to modern aireal warfare

I hate to be mean but I have to say you've absolutely no idea what you're talking about if thats what you think.

Forum: General F-22A Raptor forum

F-22 combat radius requirement