Am I the only one who's missing something?
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But in light weight situation, if the pilot breaks the rules and tries to stay nose up at 85 kt, the WOW switch may not trigger soon enough and the FLCS may loose noze authority which could end in a tail strike…
I was in a heavy-weight situation (F-16I CFT) and did not break any procedure. Started to ease the nose down at around 100kts but it wouldn’t go down. Then once I hit 90~85kts or so the nose wanted to slam down so I pulled back on the stick, apparently overcorrecting, and quickly ended up with a tail strike. I have frequently encountered situations where the nose does not want to go down at 100kts, but this is the first time such an incident resulted in a tail strike. I guess for the sake of procedure I should just let the nose gear take a beating.
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I was in a heavy-weight situation (F-16I CFT) and did not break any procedure. Started to ease the nose down at around 100kts but it wouldn’t go down. .
that is because you didnt perform the aerobraking at 13 deg AOA but at 11 or below
i didnt check the f-16CFT though as this is not original AFM included in BMS stock package
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Probably 12*. Many times when I try to do a 13* aerobrake I can’t keep it steady and it bounces between 11* and 13*.
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Probably 12*. Many times when I try to do a 13* aerobrake I can’t keep it steady and it bounces between 11* and 13*.
mhhh ? bad GC positionning on the F16 I CFT ?
did you try with a block30 or 52 ?
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Come to think of it, maybe that is it. I usually only notice it with the F-16I CFT. I’ve flown Block 40s, 50s, and 52s recently and haven’t had that problem with those Blocks.
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I thought the gun cross wasn’t supposed to exceed 12 deg on the ground, whatever AOA was. You aren’t landing on a carrier - naval craft have the super stiff gear due to that controled crash. Depending on the model 16 the struts IN REALITY may be stiffer on some, but that was due to the addition of the extra equipment carried, i.e. targeting pod mounting point strengthening, bigger under nose ducting …
But that is why you have a crew of mechanics- they are supposed to inspect the suspension, engine, wheels, batteries, etc. Every time you land your wheels go from 0 to 1xx in under a second - they scuff something beautiful - but the air pressure supporting the tire [nitrogen, whatever] help to act as part of the suspension, cushioning a little bit too. My thought is don’t worry much about slamming the nose down, the crew chief will give you a talking to if you are abusing it too badly.
-Babite
(Edit: It looks like I’m saying the pressure in the tire is acting as suspension. I mean to say the pressure gives support to the rubber tire, which acts like another piece of the suspension. Without it you’d have flat rubber smooshed against the hard ground under {X}tons of weight. Sorry about that mistake.) -
That is AoA, however we aren’t using the gun cross to determine AoA, but the AoA bracket. FPM in the middle of the AoA bracket = 13*.
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Are you measuring this on runway, or still airborne? If in air nevermind. The origional manual stated 11deg aoa @ 160kts, then flare at 100’ above the runway to 13 deg aoa GENTLY, keeping airspeed at 130kts until touchdown, with speed brakes still fully open. If you exceeded 15 aoa the speedbrakes would scrape. It was also stated to pull the gun cross to the 10 deg pitch line on the hud to aero brake, as the FPM got unreliable once on ground (weight on wheels). I know stuff has changed since that was written, the speed brake retracts some now with gear down. But you will still scrape the can reguardless of AOA if your a/c pitch on ground is above say 12 deg’s. Let the nose come down around 110 kts while you can still control the nose. Again, I realize pre-touchdown you use the bracket in the hud, but once the wheels are on the ground and your speed is slower the bracket becomes unreliable. I’m not trying to argue with your in-air procedure, just pointing out that with WOW you can only maintain so much pitch before you do dammage, the cross is more relavent on the ground to me. In theory it is where the nose is pointed - keep it as a reference. Again, appologies if I’m coming off as hostile or arrogant, not my intent. I don’t know the fall off point of the fpm on the ground, but the gun cross is constant, and AOA is a direct relationship between the two, if I recall correctly.
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Don’t worry, you’re not coming off as hostile. And you’re correct things have changed since that manual was written–personally I say scrap that part of the manual entirely because your approach/landing speed varies greatly depending on your weight, and the AoA bracket is still valid once the wheels are on the ground. Scraping only occurs at or above 15* AoA. Not sure if it’s at or above though.
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While on the ground the FPM could be wrong from wind angled down to ground or wake turbulences from another a/c. The AoA sensor is external.
The guncross is rendered somewhere at near 0* wing means incidence. The pitchladder is rendered with INS data. Both are internal.
In r/l HUD video, the FPM and AoA bracket bounce together while rolling on the ground. Looks like vibration. The top bracket of the is not always on the 13* pitchladder. Guncross/Pitchladder and FPM/AoA bracket can show different information. I’ve tried to switch to Guncross/Pitchladder but my eyes are glued to the FPM.
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Are you measuring this on runway, or still airborne? If in air nevermind. The origional manual stated 11deg aoa @ 160kts, then flare at 100’ above the runway to 13 deg aoa GENTLY, keeping airspeed at 130kts until touchdown, with speed brakes still fully open. If you exceeded 15 aoa the speedbrakes would scrape. It was also stated to pull the gun cross to the 10 deg pitch line on the hud to aero brake, as the FPM got unreliable once on ground (weight on wheels). I know stuff has changed since that was written, the speed brake retracts some now with gear down. But you will still scrape the can reguardless of AOA if your a/c pitch on ground is above say 12 deg’s. Let the nose come down around 110 kts while you can still control the nose. Again, I realize pre-touchdown you use the bracket in the hud, but once the wheels are on the ground and your speed is slower the bracket becomes unreliable. I’m not trying to argue with your in-air procedure, just pointing out that with WOW you can only maintain so much pitch before you do dammage, the cross is more relavent on the ground to me. In theory it is where the nose is pointed - keep it as a reference. Again, appologies if I’m coming off as hostile or arrogant, not my intent. I don’t know the fall off point of the fpm on the ground, but the gun cross is constant, and AOA is a direct relationship between the two, if I recall correctly.
real pilots use the AOA bracket to aerobrake at 13 AOA …so better to do the same
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real pilots use the AOA bracket to aerobrake at 13 AOA …so better to do the same
I guess if the runway is not built level and is on a 3* grade, the gunX shows 13* twhile the tail scraping at 16*.
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A 3* grade is going to be gradual over the entire distance of the runway….
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maybe “grade” is the wrong term?
If the runway is built 3° off a level plain…… -
A 3* grade is going to be gradual over the entire distance of the runway….
…and?
that still means that your AoA will be different to the elevation of the gun cross.
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This post is deleted! -
…and?
that still means that your AoA will be different to the elevation of the gun cross.
That depends on if we are talking a runway that starts from 0* and rises up to 3* at a certain point or if it is 3* in its entirety as caper said a second ago.
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well a 3 degree grade is a constant grade of 3 degrees…
in both cases, the gun cross would still be an unreliable indicator of how close you are to a tail strike.
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“Grade” refers to rise and run that creates a right triangle. It’s measured in %.
A 3° pitch = 5% grade.
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“Grade” refers to rise and run that creates a right triangle. It’s measured in %.
http://www.angelfire.com/ultra/mathproject/images/gradesign.JPG
A 3° pitch = 5% grade.
bah, this crap is why im not a rail engineer…