Forum: F-16 versus XYZ

Sorry but I just forget one or two things in my previous message. One is purely technical. The 12°AOA,9g Mach 0.72 is at sea level. Now I will say that I totally approve F-16guy comment. This is one of the reasons why the F-15/F-16 combination was so succesfull in the 1982 Lebanon conflict. The two aircrafts are so close in flight envelope that they can conduct cooperative attacks with impressive results.

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bazdriver,

Sorry to be late in responding, but I have been away for the Christmas holidays.

I agree that you and others could give me some good lessons on F-15 aero. That's why I was intentionally vague about it. I could do the same for you in regard to some F-16 characteristics. For example, the F-16 is unstable up to 0.92 mach, not 0.80. I guarantee it. And AoA has nothing to do with it.

The inlet effect is noted, but the F-15 tail is still down loaded at all positive g conditions, I believe. Also you say that the inlet effects are less at lower speeds, just where WVR usually happens, so as the fight progresses and speeds usually drop, the F-15 becomes more stable, not what you want.

So the F-15 Ps is better above 1.5 mach? Not a place where WVR normally happens, and we are talking about WVR.

The Isreali incident you mention is irrelavent to this discussion.

I have a question for you concerning OWS. When I first read of it 15 or 20 years ago, its purpose was to limit wing loads in high g rolls. Now from your comments it seems to protect the wing in symmetric turns as well. Is that true? I also question your earlier statement that the F-15 has a 9g limit at full air to air weight with OWS. Isn't it true that the OWS will give warning tones at less than 9g in some flight conditions? If so, then you cannot say the F-15 has full 9g capability. I am asking a question, not making a statement.

The F-15 wing is a nice design, but is optimized for only one thing - maneuverability. It reminds me of an F-16 wing with the LEF locked at about 8 degrees. An automatic LEF, which most if not all other modern fighters use, is clearly superior in its capability to handle many different conditions. Although not the first to have a LEF, the F-16 was the first to have an automatic maneuvering LEF.

I greatly respect your viewpoint and your opinions and would welcome more discussions. Obviously I am not a pilot, but have an engineer's perspective.

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For example, the F-16 is unstable up to 0.92 mach, not 0.80.

Ok for me. The data came from an article in Flight International Magazine.

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The inlet effect is noted, but the F-15 tail is still down loaded at all positive g conditions, I believe. Also you say that the inlet effects are less at lower speeds, just where WVR usually happens, so as the fight progresses and speeds usually drop, the F-15 becomes more stable, not what you want.

I was just puting the fact that trim drag of the horizontal tail is not as high has some might imagine.

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I have a question for you concerning OWS. When I first read of it 15 or 20 years ago, its purpose was to limit wing loads in high g rolls. Now from your comments it seems to protect the wing in symmetric turns as well. Is that true? I also question your earlier statement that the F-15 has a 9g limit at full air to air weight with OWS. Isn't it true that the OWS will give warning tones at less than 9g in some flight conditions? If so, then you cannot say the F-15 has full 9g capability. I am asking a question, not making a statement.

The OWS was from the start intended for providing warning to the pilots that they are approaching g-limit condition whatever the type of maneuver. Those limits varies with speed and weight. The OWS constantly calculates allowable symmetrical load factor using:

a)aircraft gross weight derived from the production fuel quantity system and incremented by external stores data;and

b)a Mach Number derived from the production Air Data Computer

The allowable symmetrical load factor is then decremented by an amount proportional to lateral stick position to produce the total allowable load factor. Now when you approach to max allowable G-load(92%) you get a 2Hz tone in your headset and then a 10Hz(98%). So the F-15 is not a true continuous 9g machine like the F-16 at Design gross weight. It has a small part in the flight envelope where 9g capacity is not here(known as the "thumb-print" in the flight manual).

It's the reason I do the following comment in my previous post.

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G limit advantage of the F-16 is only in a very very small part of the flight enveope.(though it can be decisive in some case).

About WVR consideration and Ps

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I mean you talk about Ps(specific excess thrust). Throughout the flight envelope the F-15 has higher values

Now the two aircraft will preferably fight at speed above 375kts and use their high Ps values in vertical maneuvers to cut lower speed adversary trajectories. But that's a personnal point of view.

Nice to see this discussion has continued, thanks for the info.

What about the Strike Eagle? If used in an Air-to-Air setup, with light weapons loading, would it be able to operate safely at higher G? I ask because the aircraft is structurally reinforced, which accounts for its much higher max payload.

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eleanordriver wrote

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Nice to see this discussion has continued, thanks for the info.

What about the Strike Eagle? If used in an Air-to-Air setup, with light weapons loading, would it be able to operate safely at higher G? I ask because the aircraft is structurally reinforced, which accounts for its much higher max payload.

Remove the Lantirn pods, remove those CFT, and a (I insist) -229 equiped aircraft is the equal of a -220 equiped A to D aircraft in the A2A arena. About the G-limit, its advantage is that (due, as you said, to the beefed-up structure) it'not subject to the "thumbprint" 9g limitation of the A-D version. So it's really a full 9g aircraft(as the F-16) at design gross weight throughout the flight envelope.

With the beefed up structure and more powerful engines, wouldn't producing more Strike Eagles be a good and cheap (relatively) suppliment to the force since the F-22 is going out of production due to bad press and the F-35 is going to be delayed. Strike Eagles could be an adaptable force if produced with the intention of being used as air-to-air fighters with equipment stripped off or Deep Strike aircraft when loaded.

Why strip the strike eagle? Would you rather take off with 1-3 gas bags that you are not allowed to drop and cause you to only gain the benefit of half the gas inside, or have the same amount of fuel as two and a half in a package that has less added drag then one?

WOW. Thanks to Bazdriver and Johnwill for a fascinating exchange. Not being an expert in this area, I could only understand about 1/3 of what you were both discussing but I learned a lot. The fact that you were both respectful and collegial shows that you're both not only highly intelligent and experienced but people of good character as well. THIS is why I LOVE F-16.net!!!

Thanks Psychmike!

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Why strip the strike eagle? Would you rather take off with 1-3 gas bags that you are not allowed to drop and cause you to only gain the benefit of half the gas inside, or have the same amount of fuel as two and a half in a package that has less added drag then one?

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With the beefed up structure and more powerful engines, wouldn't producing more Strike Eagles be a good and cheap (relatively) suppliment to the force since the F-22 is going out of production due to bad press and the F-35 is going to be delayed.

I will not be long because the question of eleanordriver is calling an other topic. I will give my vote to sprstdlyscottsmn. Any F-15I driver will concede that it can not tangle with a Baz or Akef in the knife fight regime, but to get here, you have to defeat its weapons system. Now ,even in WVR, never forget that F-15I like F-18F have two pilots with each of them with DASH/JHMCS, that can independently track and slave a AIM-9X/Python 5 to two seperated targets,

Now concerning the USAF, even if I'm a true F-15 lover and considering it a more capable platform, I think they should preferably buy F-16 block50/52 or 60 if a stop gap mesure is needed. They are much less costly to operate in most missions.

bazdriver, forgive me for asking, but I can't seem to find what an Akef is. Can you help me out? And I certainly agree with you about the twin pilot issue, those extra eyes alone are worth the 500lbs of gas in a high threat environment. Does the Ra'am have better radar than the Baz?

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sprstdlyscottsmn
Posted: Jan 26, 2010 - 05:05 AM

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bazdriver, forgive me for asking, but I can't seem to find what an Akef is. Can you help me out? And I certainly agree with you about the twin pilot issue, those extra eyes alone are worth the 500lbs of gas in a high threat environment. Does the Ra'am have better radar than the Baz?

Hello Sprstdlyscottsmn. Sorry to be late.

In Israeli Air Force

F-15A/B: Baz (Falcon)
F-15C/D: Akef(Buzzard)
F-15I: Ra'am (Thunder)

The radar. hmm. Actually F-15 most Baz and Akef are equipped with APG-63 nearly equivalent to APG-63 V(1), which in turn is better A2A than the APG-70 and is also equipping F-15K if I remember. But some specific modes are deleted in comparison to USAF one's. Maybe, a further upgrade can involve APG-63 V(3) (though certainly a degraded one) or an Elta alternative to both the Akef and Thunder.Maybe...(F-35 availability and price would be determinent).
Baz are too old in terms of economical value for a further upgrade of radar.

Okay, thanks, that clarifies a lot for me.

Forum: F-16 versus XYZ

F-16 VS F-15 WVR