FY2020 DoD Budget

sprstdlyscottsmn · by **sprstdlyscottsmn** » 22 Apr 2019, 16:35

The F-15 RCS is a bold faced lie as well. 42.8 ft is just under 4m^2. Doubly misleading is indicating that RCS is for a Beast Mode F-15. Plenty of reports have shown that F-15s are on the order of 25m^2 clean. Beast mode would be closer to 42.8m^2 than 42.8ft^2.

usnvo · by **usnvo** » 22 Apr 2019, 17:12

sprstdlyscottsmn wrote:The F-15 RCS is a bold faced lie as well. 42.8 ft is just under 4m^2. Doubly misleading is indicating that RCS is for a Beast Mode F-15. Plenty of reports have shown that F-15s are on the order of 25m^2 clean. Beast mode would be closer to 42.8m^2 than 42.8ft^2.

"Never attribute to malice that which is adequately explained by stupidity." Hanlon's Razor. I doubt it is a lie, or at least not on the part of USAF Magazine, merely incompetence.

Look at the graph, obviously generated by someone with no familiarity in the topic. Beyond mixing units of measurement in their RCS comparison (metric and standard), they also use a linear measurement instead of an area measurement as would be required for RCS. So right off the bat they have no credibility. But beyond that, which is pretty damning, they also show combat radius without any qualifiers but it is clear they are talking about different missions, provide dollar figures that don't match the budget books (including that they are only estimates and don't include engines or GFM in the case of the F-15X), and show different missions for the aircraft although if the F-35A was to replace the F-15C instead of a F-15X, it would perform the exact same mission.

sprstdlyscottsmn · by **sprstdlyscottsmn** » 22 Apr 2019, 17:21

usnvo wrote:"Never attribute to malice that which is adequately explained by stupidity." Hanlon's Razor. I doubt it is a lie, or at least not on the part of USAF Magazine, merely incompetence.

Fair enough. As you pointed out there are a LOT of errors and inconsistencies.

spazsinbad · by **spazsinbad** » 22 Apr 2019, 17:26

sprstdlyscottsmn wrote:
usnvo wrote:"Never attribute to malice that which is adequately explained by stupidity." Hanlon's Razor. I doubt it is a lie, or at least not on the part of USAF Magazine, merely incompetence.

Fair enough. As you pointed out there are a LOT of errors and inconsistencies.

Ya just gotta luv the interbabble. :doh:

marsavian · by **marsavian** » 22 Apr 2019, 19:21

The future viability of F-15EX against serious opposition rests entirely on how effective EPAWSS can be in protecting it from radar. From my understanding it will be spherical in its coverage and will send deception jamming back on receiving radar pings. How effective that will be remains to be seen.

marauder2048 · by **marauder2048** » 22 Apr 2019, 20:10

marsavian wrote:The future viability of F-15EX against serious opposition rests entirely on how effective EPAWSS can be in protecting it from radar. From my understanding it will be spherical in its coverage and will send deception jamming back on receiving radar pings. How effective that will be remains to be seen.

Which explains why the F-15EX was requested before EPAWSS even flew...

And that does nothing for the IR spectrum where the F-15 is a big, hot target.

weasel1962 · by **weasel1962** » 23 Apr 2019, 01:39

Good to know the Niratam difference is that high. Explains all the F-15s lost to IR missiles over the past few decades.

Also good to know that an engine that has a 3600 deg TIT has a smaller IR signature than engine that has a <2500 deg TIT. Astounding US only physics.

Corsair1963 · by **Corsair1963** » 23 Apr 2019, 01:50

deleted

spazsinbad · by **spazsinbad** » 23 Apr 2019, 01:58

Am I dreamin' or was above posted previous page: viewtopic.php?f=58&t=55106&p=417227&hilit=Tirpak#p417227

Corsair1963 · by **Corsair1963** » 23 Apr 2019, 02:18

As usual much of the information is inaccurate or at very least "misleading"! Especially, in regards to Range, Payload, and Top Speed.

http://www.airforcemag.com/MagazineArch ... al.v30.pdf

marauder2048 · by **marauder2048** » 23 Apr 2019, 02:23

weasel1962 wrote:Good to know the Niratam difference is that high. Explains all the F-15s lost to IR missiles over the past few decades.

Also good to know that an engine that has a 3600 deg TIT has a smaller IR signature than engine that has a <2500 deg TIT. Astounding US only physics.

You've had at least two instances of friendly IR AAMs damaging or destroying F-15s.
The F-15S hit by the IIR AAM-as-SAM over Yemen looks like a hull loss.

More to the point, radiation intensity is radiance * projected area which is why aircraft skin temperatures
due to aero-heating will dominate (for most of the threat viewing angles and most engine power settings)
over the engine casing even though the latter is hotter.

weasel1962 · by **weasel1962** » 23 Apr 2019, 03:58

For the rest of us that live in the real world, the biggest IR signature comes from the engine. How many of those "numerous" F-15 losses have not come in the direction of the tailpipe?

A higher bypass ratio might help to cool down the engine. Engine deflectors like those on the f-22 helps significantly. However the F-35 has an engine that is way hotter (for a simple fact to generate more thrust) and has a lower bypass ratio than the F-110 which means the F-110 can cool better. Its very easy to ignore fact when trying to demonise anything but demonising a plane that is served with pride as a primary interceptor sounds ridiculous.

And of course, fact doesn't count with magic planes. Might as well argue the magic plane does not emit any engine plumes.

wrightwing · by **wrightwing** » 23 Apr 2019, 04:10

weasel1962 wrote:For the rest of us that live in the real world, the biggest IR signature comes from the engine. How many of those "numerous" F-15 losses have not come in the direction of the tailpipe?

A higher bypass ratio might help to cool down the engine. Engine deflectors like those on the f-22 helps significantly. However the F-35 has an engine that is way hotter (for a simple fact to generate more thrust) and has a lower bypass ratio than the F-110 which means the F-110 can cool better. Its very easy to ignore fact when trying to demonise anything but demonising a plane that is served with pride as a primary interceptor sounds ridiculous.

And of course, fact doesn't count with magic planes. Might as well argue the magic plane does not emit any engine plumes.

More thrust doesn't automatically = higher IR signature.

marauder2048 · by **marauder2048** » 23 Apr 2019, 04:20

weasel1962 wrote:For the rest of us that live in the real world, the biggest IR signature comes from the engine.

Those of us who care about all-aspect threats, you know like practically every IR threat since the late 70's
worry about those other signatures.

weasel1962 wrote: How many of those "numerous" F-15 losses have not come in the direction of the tailpipe?

Irrelevant since the two hit by friendly air-to-air IR were hit by all-aspects IR missiles. So was the F-15S over Yemen.

weasel1962 wrote:A higher bypass ratio might help to cool down the engine. Engine deflectors like those on the f-22 helps significantly. However the F-35 has an engine that is way hotter (for a simple fact to generate more thrust) and has a lower bypass ratio than the F-110 which means the F-110 can cool better.

Displays a complete lack of understanding about how plume signature reduction is achieved on the F-35.

weasel1962 wrote:Its very easy to ignore fact when trying to demonise anything but demonising a plane that is served with pride as a primary interceptor sounds ridiculous.

If it's primary role is claimed to be that of an interceptor then frontal IR signature is even more important
than plume reduction.

weasel1962 wrote:And of course, fact doesn't count with magic planes. Might as well argue the magic plane does not emit any engine plumes.

One was the beneficiary of a massive effort to reduce plume signature. One wasn't. Which is going to be more useful?

weasel1962 · by **weasel1962** » 23 Apr 2019, 06:31

The F-135 is a much hotter engine with a lower bypass ratio no matter how somebody tries to spin it.

F-15 today hasn't benefited at all? Same engines today as 1970? lol.

The fact is that the USAF and USN still has 2000 of these legacy big hot targets in service. All doomed based on IR according to a junior LM marketeer.