Threshold Speed
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Don’t worry about the backwards thing, It was just banter. It is backwards, but only when you compare it to most other aircraft. Do I care? No… I just don’t use it. All that “backwards” stuff is just a fun excuse to bring some other interesting info people may not have considered.
Sounds like you’re a Navy guy…I do the same as you - ignore the bracket and use the indexer.
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Why “nose in the direction of the arrow/throttle in the direction of the light” works - if you are over/under-shooting you can use your nose (attitude) to control your ground speed and open/close distance on the CV or runway while maintaining glide slope.
I use this with BMS too, to drag or push the 2.5 degree dashed pitch line into the VASI if I am overshooting or undershooting my desired touchdown point, but because I’m shooting a runway I can be more drastic with my adjustments. Other than the colors you can read and use the indexers in the Viper and the Hornet the same way - they tell you the same thing. It’s just the HUD indication that differs, and personally ignore the Viper bracket once I’ve captures on-speed - I use the indexer…can’t go wrong in either, that way. Keep in mind that it’s a balancing act between power/speed/attitude to maintain any given AOA, and that to catch a wire attitude is critical.
As for the HUD bracket - it sort of makes sense that they are reversed depending on what is of most import on landing - speed or attitude. During one of my adventures in the T-45A sim I was overshooting the CV slightly coming over the round down…being better to miss high than low, I went to full power to go around - but I made one fatal mistake…I checked the stick back instead of holding what I had to fly away. Everything went red and I was suddenly about 60 degrees nose down looking at the deck. “You caught a 3 wire”…inflight engagement - BAD.
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Sounds like you’re a Navy guy…I do the same as you - ignore the bracket and use the indexer.
I don’t see any difference between the bracket and the indexer…they indicate the exact same value : the AOA
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By the same logic you don’t see the difference in a speedometer that goes clockwise or counter-clockwise.
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that means the F16 indexer has to be seen more as a STICK ACTION than a THROTTLE action and colors fits the AOA indicator stripe
PERIOD.From that perspective indeed, the NAVY AOA indexer is not working the same , IIRC colors are not the same and arrows are about THROTTLE ACTION rather than STICK action…
Very true. Glidepath in the Hornet is controlled primarily with power, so the difference has a valid justification. The lower approach speed (no landing flare) leads to an approach flown further left on the thrust required curve… more firmly in the “region of reversed command.”
Power moves the E-bracket up or down, just as it will do to the Velocity Vector, as that is the most direct control of glideslope in the Hornet. The E-bracket moves like a “magnified” VV, making every small change in alpha that is already visible (in the difference between waterline and VV) even more visible. By contrast, the indexer is a “directive.” If the lower light is illuminated, higher alpha is required, and the hand motion for both stick or throttle to increase alpha is aftward. Together they serve to increase awareness of the rate of change of alpha and (just like the Viper’s presentation) eventually make corrections almost subconscious.
Not sure if it’s exactly relevant, but for Navy AC the runway is constantly moving away from them at ~30 knots (or they are trained to act as if it is). Which means you’d have to keep the FPM where the deck will be when you touch down. I am fairly certain the Navy strongly discourages this (spotting the deck) and insists you fly the meatball and the AoA indicators.
Exactly. Only exception to that doctrine I know of is a Case III (ILS) approach, where the pilot is flying the needles.
There are some goofy posts in this thread, but bottom line is that it’s just two different representations of the same information designed to fit a particular mode of operation. Each jet’s representation makes sense.
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I don’t see any difference between the bracket and the indexer…they indicate the exact same value : the AOA
Not really - the bracket indicates an acceptable range of AOA for your given pitch attitude that will keep you on-speed. That’s not the same as actual AOA.
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The only real compensation made for the runway “moving away from you” is flying a circular vice box landing pattern…I never could figure out how this worked until I got in the T-45A sim at Navy Kings and tried it out myself. Works like a charm.
BTW - the T-45A doesn’t have a FPM or VV - just a waterline symbol (in fact, the syllabus at the time called for not even allowing the student to turn the HUD on until after his first CV cycle; I guess to force them to rely on the indexer)…so I initially taught myself to hook the wrong way…by spotting the deck, even though I was on-speed doing so (which was also why I couldn’t do it at night, I suppose). And as such I couldn’t hit the FCLP spot ashore - I found it far easier to hit the ship than the no-moving spot. Until one of the pilots showed me how to fly the pattern by the numbers vise eyeballing it, and I hit the spot first try while he was watching.
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The only real compensation made for the runway “moving away from you” is flying a circular vice box landing pattern…I never could figure out how this worked until I got in the T-45A sim at Navy Kings and tried it out myself. Works like a charm.
This is not true at all and not the purpose of the racetrack pattern. The ship is aligned to put the relative wind down the angle as best as possible, but if the ship is “making its own wind” (steaming windward) it will be mis-aligned and require the pilot to constantly correct to the right. This is a common case. A racetrack pattern is used because it is more compact and more fluid, allowing for constant corrections to arrive in the correct position at the start. I don’t know where you’re getting this stuff.
Not really - the bracket indicates an acceptable range of AOA for your given pitch attitude that will keep you on-speed. That’s not the same as actual AOA.
He’s using “exact same” as a figure of speech… meaning that the indexer and bracket are for the same purpose.
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I get it from Navy guys that do for a living…and doing it in the trainer myself. Yes - the ship steers into the wind. But when you break across the bow and fly a circle vise box pattern the ship/touchdown point have moved to be in the position of your baseline course by the time you get to the groove - which is why it works, and works very well.
Read up on it in the CV NATOPS for yourself…
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This is not true at all and not the purpose of the racetrack pattern. The ship is aligned to put the relative wind down the angle as best as possible, but if the ship is “making its own wind” (steaming windward) it will be mis-aligned and require the pilot to constantly correct to the right. This is a common case. A racetrack pattern is used because it is more compact and more fluid, allowing for constant corrections to arrive in the correct position at the start. I don’t know where you’re getting this stuff.
He’s using “exact same” as a figure of speech… meaning that the indexer and bracket are for the same purpose.
It’s actually possible to steer the boat such that the vector addition of the ship’s motion and the wind vector combine through vector addition to make the wind aligned with the angled deck. If I remember the deck is angled 17°. If the ship goes forward 25 knots and the wind is 11 knots then you steer 44 degrees right of the eye of the wind. The total wind would be aligned with the deck.
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I get it from Navy guys that do for a living…and doing it in the trainer myself. Yes - the ship steers into the wind. But when you break across the bow and fly a circle vise box pattern the ship/touchdown point have moved to be in the position of your baseline course by the time you get to the groove - which is why it works, and works very well.
You could also manipulate a rectangular type pattern to arrive at the start in the correct position, it would just require too much space and would not enable small adjustments. Fixed-wing recovery procedures are designed for efficiency and precision, hence the racetrack type pattern. Let me know if you can back up your statement, because CV NATOPS does not (to my knowledge. I’ve read it a few times.)
It’s actually possible to steer the boat such that the vector addition of the ship’s motion and the wind vector combine through vector addition to make the wind aligned with the angled deck. If I remember the deck is angled 17°. If the ship goes forward 25 knots and the wind is 11 knots then you steer 44 degrees right of the eye of the wind. The total wind would be aligned with the deck.
Absolutely, but if there is not sufficient wind over the deck, the boat will “make its own wind” by sailing faster, which it cannot do along the angle deck. That necessarily introduces crosswind for the pilot to counteract. See page 4-10 http://www.cnatra.navy.mil/pubs/folder5/T45/P-1211.PDF I don’t think Stevie’s T-45 sim ride involved this.