Sweetie: How to land a jet plane on an aircraft carrier

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[Sweetie wrote this for some online thingie.]

In some ways aircraft carrier landings are a zen experience. For the fifteen to twenty seconds you are on final approach, there are only three things in the entire universe you care about: Meatball, lineup, and angle-of-attack. Everything else fades into irrelevance. It's a very simple existence.

But we'll come back to that. I should probably explain how you get yourself set up in such a situation.

First, you'll have to join the Navy. And you can't just enlist, either - you have to be a commissioned officer...

Okay, I'll skip forward a bit. Carrier qualification comes quite far into your training as a Naval Aviator. You'll have had an extensive ground school, on the order of about 150 hours of dual instruction, a couple of dozen hours solo. You'll have gone through an intense syllabus in instrument flying, aerobatics, and formation flying. You'll have completed a dozen or so flights devoted to fclp ("field carrier landing practice") during each of which you will have done a dozen or so practice approaches to a carrier deck sized box painted on the runway, with every landing graded by the landing signal officer, or LSO. You have to convince the LSO that you won't kill yourself or scare anyone unduly before they let you fly out to the ship for real.

The daytime traffic pattern at the carrier is an ovoid "race track" with the downwind leg at 600 feet, 180 degrees opposite to the "Base Recovery Course" on which the ship is steaming. (Procedures at night are totally different, and I'm blowing them off for this w/u.) Civil aircraft and the Air Force practice a box-shaped traffic pattern, with crosswind, downwind, base, and final approach legs. The Navy, though, has found that timing, spacing, and interval are more easily controlled with the race-track pattern, where the planes make a constant, semi-circular turn from the downwind leg to the final approach.

You enter this traffic pattern by flying at 800 feet right up the wake of the ship, passing close-aboard to starboard. You'll be at about 250 knots, or faster if you're a show-off, and, unless the plan is for "touch-and-go" landings, your tailhook will be down. You must spot any other traffic in the pattern, and extend upwind appropriately to allow the proper time interval. You must allow any plane ahead of you from 30 to 45 seconds, to give them time to taxi clear of the landing area and reset the arrester gear.

Now comes the fun part. It's called a "break" turn. It's a full aileron-deflection snap roll over to a 70 to 90 degree angle of bank, accompanied by a chop of the throttle to idle, and extension of full speed-brakes. This should be a very crisp, head-snapping maneuver. You are being watched, after all. As you bank over, you pull back the stick to about a 3 to 4 'g' pull. You must be careful to keep this high-g turn level. You will swiftly decelerate to the airspeed at which you can extend the landing gear and flaps. And you must be very careful to roll out of this turn on the proper reciprocal, downwind heading. As you slow down and approach the proper heading for the downwind leg, you can descend out of 800 feet for 600. After gear and flap extension you decelerate even more rapidly. You must come back up on the throttle to halt this deceleration at the proper speed for the approach (on which more in a moment.) You will be constantly trimming the aircraft as appropriate for the landing configuration. Once established on the downwind leg, you will complete your landing checklist. It should be apparent that you have an awful lot to do in a very few seconds.

Now, the "Navy way" here is to decelerate to and maintain the optimum airspeed for final approach. The complication is that this airspeed varies rather widely with things like remaining fuel load, unexpended ordnance, and so forth. So you don't use your airspeed indicator. You use an "angle-of-attack," or AOA indicator, which measures the angle at which the airfoil of the wing meets the oncoming airstream. It's a little bit of aerodynamics for business majors, but there is an optimum AOA you can fly that will put you at the optimum approach airspeed, no matter what your aircraft's gross weight. The indicator you use for this is a small array of colored lights atop your instrument panel, arranged thusly:

v

o

^

If the center 'o', colored yellow, is lit, you're 'on speed', or at the proper AOA. If the upper chevron, colored red, is lit, you are slow, and must pitch the airplane nose-down a bit to speed up. If the lower chevron, colored green, is lit, you are fast and must pitch nose-up a bit.

And here we get into what was, for me at least, a little counter-intuitive. Because you control your airspeed with your pitch attitude, and you control your rate of descent with the throttle. It seems a little backwards, doesn't it?

If you've done everything right, you'll pass down the ship's port side at about 1 to 1.25 miles. You begin your turn to final approach when "abeam" the stern of the ship (this position is called the "one-eighty" because you have that many degrees to turn...except that's not exactly true, as I'll describe in a moment...)

You should be "on speed" and trimmed up for hands-off flight. You pull back the throttle just enough, while maintaining your AOA by minute pitch angle changes so that the aircraft attains about a 250 foot per minute rate of descent. You establish maybe a 15 degree angle-of-bank turn. I always used to take one last quick glance at the landing-gear indicators to make sure all three were down and locked.

And you basically "hold what you got" until the "90", which is 90 degrees of turn off the downwind heading. You should be passing through 450 feet altitude, still on speed. Your rate of descent, again controlled by the throttle, can increase to 400-450 feet per minute. The plane ahead of you in the traffic pattern should be touching down. Don't look at him, you've gotta pay attention.

At the "forty-five" (I bet you can guess where this is in the pattern) you should start to pick up the "meatball," AKA the optical carrier landing aid. This is basically a Fresnel lens, described in another write up, but the upshot is that there's a light array, about 6 feet high, just to the left of the landing area on the flight deck. It has a horizontal row of green lights, called the "datum lights", and an orange light, or "meatball," that rides up and down to indicate your situation relative to the optimum glideslope, for example:

| |

| |

ooooOoooo

| |

| |

...indicates you're on the 3-degree glide slope, and...

| |

|O|

oooo oooo ...indicates you're above it.

| |

| |

...Also, the lowest cell on the display is red, to indicate that you're about to be in trouble. The Landing Signal Officer, or LSO, will invariably give you a "wave-off" if you're too low. He does this by triggering a button on a hand-grip he holds, (called the "pickle".) This makes the the meatball array flash , and is your signal to add full throttle, abort the descent, climb back up to the traffic pattern, and go around for another try. As I say, you'll begin to pick this display up at around the "forty-five" position. You'll announce that you see it with a very concise radio announcement, as follows:

"...Gambler 703, Viking ball, 8.6"

Which translates to: This is Gambler 703 (Gambler would be my squadron callsign, 703 would be the number painted on the tail), I DO see the ball, and I'm an S-3 Viking, and I've got 8600 pounds of fuel remaining.

The LSO will reply: "Roger ball."

You'll continue turning and descending. If you're high you'll increase descent by pulling back on the throttle while maintaining optimum AOA. If you're low you'll decrease rate of descent by advancing the throttle, again maintaining optimum AOA. When the meatball is properly centered, you'll make appropriate throttle adjustments to re-establish the proper rate of descent to stay on the glideslope. Minute stick and throttle adjustments are constant from this point forward. They must be subconsciously automatic, which is one reason why you did so many practice approaches back at the field.

And at this point you've also reached your final approach heading, and should roll out of your bank. You should be established on the extended center line that runs down the landing area on the flight deck.

Which, as I hinted earlier, is NOT aligned with the course the ship is steaming! Modern carriers have angled flight decks...the landing area is canted 10 degrees to PORT of the ship's keel (and the course it steams on). This is so that, if you miss a wire, you can simply roll off the end of the angled landing area, safely clearing the planes parked on the ship's bow, and go around again for another try. This means that, as you approach the final leg, you'll cross the ships wake at a shallow angle, and continue your turn for another 10 degrees to align with the landing area. This also means that, as you come down on final, the ship is constantly moving from your left to your right. So you have to make tiny, subtle corrections to stay on the proper line-up. Aren't you glad you signed up for this duty?

So now you're on final approach, about 15 to 20 seconds out. An ideal carrier landing will be a ride down a 3-degree glide slope all the way to touch down...the pilot will see a centered meatball with no deviations, and airspeed will stay "pegged" at the optimum AOA. To maintain this you'll have to make constant, rapid, tiny corrections. You do NOT look at the landing area - this is called "spotting the deck," and is a no-no. The plane ahead of you will either taxi clear of the landing area in time, or not. If he doesn't, the LSO will give you a wave-off, and you'll go round for another try. Your attention constantly bounces from the meatball, to your line-up, to your AOA gauge. Ahh, this is sublime.

There is no "flare" at the end of the approach like you see airliners, light planes, and air-force pilots do. You fly the glide-slope until the deck gets in the way. So you hit the deck with a good solid thump. And, since you're watching the meatball, not the deck, the exact moment of every landing is a surprise. The ship has four arrestor wires, and, if you do it right, you'll put the point of your tailhook down in the middle of them, i.e., between wires 2 and 3. The ideal landing is therefore a "3-wire".

At the moment of touchdown, you do another thing that's a bit counter-intuitive when you first learn of it: You JAM FULL THROTTLE!

This is because your hook can MISS the arrestor wires. In fact, you can make a PERFECT approach, and your hook can occasionally bounce over the wires. This is called a bolter, and it's no big deal provided you can climb away as you roll off the end of the landing area. Jet engines can take a few seconds to "spool-up" to full power, though (they've gotten a lot better in recent years; the early ones were really dangerous). So you want to apply full-throttle on touchdown in anticipation. The arrestor wires will still stop you just fine, even at full throttle. Only once you're sure you're aboard do you pull throttle back to idle, and look for the "yellow-shirt" for taxi direction to your parking spot.

And it is, as they say, an "E" ticket ride. You go from around 140-150 mph (a bit slower, maybe 130 in S-3's) to a dead stop in a bit over a second. When you CQ, or carrier qualify, you typically have to do 5 or 6 of these in succession...which means you trap, then launch from the catapult, go back around immediately and do it again. Back in the day I was, as they say, a whisper-thin lad, and I'd always have bruised collarbones from the shoulder-straps at the end of the day. And, of course, EVERY approach is graded; the LSO de-briefs you on any excursions you made from an optimum approach (they have their own shorthand notation they use to denote and record this). They're very hard to please; the BEST grade you can get on an approach is called "OKAY". Or, sometimes, an "OKAY UNDERLINED" for emphasis. Or, you can get a "Fair." Or, if you're flailing, you'll get a "no-grade." Get too many of those and you're looking for other work.

And they post the grades for every pilot, no matter the rank, on a "greenie board" in your squadron's ready room. Junior officers can and do out-score senior ones, and, yes, it can be awkward. But the system has an integrity that you have to respect, becuase if you screw up too badly, you die.

And sometimes, you can do everything PERFECTLY and STILL die.

-- Anonymous, November 05, 2002

Answers

gives new meaning to 'dropping out' doesn't it?

-- Anonymous, November 06, 2002

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