This is a discussion on Will the F-35 replace the F-15 in the USAF? within the Air Force & Aviation forum, part of the Global Defense & Military category; @Zaphael
With respect to Reply #72,
Take a look at this:
AIM-54 Phoenix Missile
An enemy missile like the Phoenix ...
An enemy missile like the Phoenix might be a potential threat for even a F-35 in full afterburner at it's absolute ceiling.
Not that I know so much about, say, Russian SAM's but a Phoenix round should be able to merely knock a recon Mig-25 out of the sky by weighing several hundred pounds at burnout and ploughing into the MIG from any direction.
In this case supercruising may not be an advantage. But, I agree ahead of time: That's what Electronic Countermeasures are for, right? I admit I haven't studied that subject because it's usually highly classified, for good reason.
As for the redline speed of the F-35/F-22 duo, that should be officially classified. I still need to get my Sandisk out and look at some NASA Boieng 2707 reports concerning the GE and P&W engines. Performance graphs were given in the reports and they're still on the 'Web.
I'll need to extrapolate the figures for a smaller generic thrust vectored engine that's on those fighters. The officially quoted thrust should be about a maximum of 35,000 lbs at sea level for the Raptor and Lightning II.
An enemy missile like the Phoenix might be a potential threat for even a F-35 in full afterburner at it's absolute ceiling.
Not that I know so much about, say, Russian SAM's but a Phoenix round should be able to merely knock a recon Mig-25 out of the sky by weighing several hundred pounds at burnout and ploughing into the MIG from any direction.
In this case supercruising may not be an advantage. But, I agree ahead of time: That's what Electronic Countermeasures are for, right? I admit I haven't studied that subject because it's usually highly classified, for good reason.
As for the redline speed of the F-35/F-22 duo, that should be officially classified. I still need to get my Sandisk out and look at some NASA Boieng 2707 reports concerning the GE and P&W engines. Performance graphs were given in the reports and they're still on the 'Web.
I'll need to extrapolate the figures for a smaller generic thrust vectored engine that's on those fighters. The officially quoted thrust should be about a maximum of 35,000 lbs at sea level for the Raptor and Lightning II.
The AIM-54 isn't in service anywhere (except possibly a few rounds in Iran, assuming they're still in good enough condition to be fired, and that's a big assumption) and from what I understand was designed to intercept high flying Soviet bombers, not fighters and especially not LO aircraft. It probably wouldn't do too well against a manoeuvring, low-observability target. How one would attain a firing solution on an F-35 using the Phoenix while somehow remaining out of reach of the F-35 (and the warfighting system of which it is a part) would be a difficult question to answer too. If your point was more about missiles like the AIM-54 rather than the AIM-54 itself, then I apologise for the unnecessary response.
Also if you're attempting to figure out speed and acceleration and so forth for aircraft, would I be correct in saying that thrust-to-drag ratio is as or more important than thrust-to-weight (I have no idea about these things so was hoping you could tell me, as you seem to understand them)? If so, how do you calculate the drag of a given airframe, along with changes in configuration (pylons, external stores etc)?
An enemy missile like the Phoenix might be a potential threat for even a F-35 in full afterburner at it's absolute ceiling.
Not that I know so much about, say, Russian SAM's but a Phoenix round should be able to merely knock a recon Mig-25 out of the sky by weighing several hundred pounds at burnout and ploughing into the MIG from any direction.
In this case supercruising may not be an advantage. But, I agree ahead of time: That's what Electronic Countermeasures are for, right? I admit I haven't studied that subject because it's usually highly classified, for good reason.
As for the redline speed of the F-35/F-22 duo, that should be officially classified. I still need to get my Sandisk out and look at some NASA Boieng 2707 reports concerning the GE and P&W engines. Performance graphs were given in the reports and they're still on the 'Web.
I'll need to extrapolate the figures for a smaller generic thrust vectored engine that's on those fighters. The officially quoted thrust should be about a maximum of 35,000 lbs at sea level for the Raptor and Lightning II.
I think Bonza has made an adequate reply wrt to the AIM-54 missile. The missile has to be given an initial targeting information via the aircraft fire control radar, and updated by it until the missile has reached a range where its own active radar can take over. That applies for the AIM-120 missile as well.
With the Raptor and hopefully the F-35, they won't be detected at long distances that allow such shots to be taken at them.
When it comes to missile defense, theres definitely more than one approach. Staying out of the missile/threat's weapon engagement zone is one of them. That is where intelligence is needed about the type and capability of the threat. The other is like you said, via ECM, where you flood or spoof their radars with a barrage of noise or false signals, if possible damaging their circuitry completely. And finally, when it comes to an actual shot being taken, speed and acceleration is needed to defeat the missile.
Simply put, a missile regardless of type, will have less fuel than the aircraft its targeting. By running away from a Mach 4 missile at Mach 1.5, the closure rate of the weapon is reduced to 2.5 Mach. And the missile will chase to a point where its own fuel expires, and it relies solely on kinetic energy to reach its target that is fleeing. By applying a series of manuevers, the defending jet can drain away that missiles KE to a point that it can no longer make the intercept. This is why having a lot of acceleration is important; to quickly create that reduced overtake by the missile so that you have time to outlast the missile's fuel. This is the same for both A2A missiles and SAMs. Definitely, there will always be that point in the sky where the jet is simply too close to the threat that no matter how he manuevers, the missile will always have the energy to make the intercept. This is called the no-escape-zone.
Can supercruise be an advantage in missile defense? Yes, but I doubt the pilot will simply be supercruising if a missile shot is coming his way. The balls will go to the wall, in order to buy as much time as possible.
At the end of the day, an aircraft's redline speed is not used reached often even in combat. Mainly because it takes too long to "get there" and it sucks up too much fuel. Hence there is little utility in the "redline" speed unless somethings going really really wrong, I guess you'd be able to understand that since you can sort of imagine the type of curve you'd get if u plot out acceleration in speed vs time graph. Its steep initially, and sort of just tapers out flat before it reaches the redline. That tapering out is not where the acceleration is the most useful, but the nice steep regions before that.
As for scrappy's post, I'm not sure what he was talking about. Most SHORADS or MANPADS I know don't reach up to 60,000ft. That kinda altitude envelope is more common for fixed and semi-mobile ADS systems like the Patriot or S-300s.
I think Bonza has made an adequate reply wrt to the AIM-54 missile. The missile has to be given an initial targeting information via the aircraft fire control radar, and updated by it until the missile has reached a range where its own active radar can take over. That applies for the AIM-120 missile as well.
I admit ignorance to the subject of Russian SAM's in the past, since I thought there was going to be a lot of speculation about something the Russians probably deem more highly classified to their national defense than we do.
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With the Raptor and hopefully the F-35, they won't be detected at long distances that allow such shots to be taken at them.
Indeed, yes. ECM can help some if one know the capabilities of Russian SAM radar sets.
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And finally, when it comes to an actual shot being taken, speed and acceleration is needed to defeat the missile.Simply put, a missile regardless of type, will have less fuel than the aircraft its targeting. By running away from a Mach 4 missile at Mach 1.5, the closure rate of the weapon is reduced to 2.5 Mach. And the missile will chase to a point where its own fuel expires, and it relies solely on kinetic energy to reach its target that is fleeing. By applying a series of manuevers, the defending jet can drain away that missiles KE to a point that it can no longer make the intercept. This is why having a lot of acceleration is important; to quickly create that reduced overtake by the missile so that you have time to outlast the missile's fuel.
The Americans should be going to great lengths to achieve a goal of both ECM and evasive aircraft actions. I agree.
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Can supercruise be an advantage in missile defense? Yes, but I doubt the pilot will simply be supercruising if a missile shot is coming his way. The balls will go to the wall, in order to buy as much time as possible.
Evasions---and especially---afterburners will shorten range. Not a good idea unless the pilot is forced to do that.
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At the end of the day, an aircraft's redline speed is not used reached often even in combat. Mainly because it takes too long to "get there" and it sucks up too much fuel. Hence there is little utility in the "redline" speed unless somethings going really really wrong, I guess you'd be able to understand that since you can sort of imagine the type of curve you'd get if u plot out acceleration in speed vs time graph.
I agree with practically everything above. In particular, and to make the assertion, the possible maximum speed of the newest planes and Century Series were higher than advertised, which was intentionally set forth by the Pentagon/Cia/etc. to understate classified info.
Running out of time in this borrowed computer on Sunday. I'll have several hours on Monday evening to get to my calculated "redline" speeds and ceilings of the F-35 and possibly other older planes.
From memory, the J75 of the F-16 would produce 5000 lbs of thrust at Mach 2.5 at 75,000 ft.
(I saw this in either an old book or Gov't report years ago, but it surprised me so much, I never forgot it.)
It's a point of extrapolation for something like a F110, for starters, but I look further.
