Avoiding a Belly Slide

Gear-up landings are an expensive embarrassment that wont happen with just a little discipline

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It was almost sunset when I came out to the field. I needed to pick up my Jepps that I had left in the airplane. I came out the side of the hangar, facing the runways. It was then that I noticed the Beech Travelair sitting like a duck, bedded down for the night, landing gear neatly recessed into the wheel wells. Gear-up on our least-used runway.

There were red caution strobes all around the Travelair, so incoming traffic (rare at night) would see the bird. I picked up my flashlight and went out for a look. Streaks of oil, rubber and metal trailed out behind the twin. A classic gear-up, but why? I put on my sleuth hat and looked around. People, parts, position and paper – the classic aircraft accident investigation probes, ran through my mind. About that time, the security guy, Mike, drove up.

What happened? I asked.

I dont know all of it. I came on shift and started out to do my taxi way and runway check, before the tower closed down. I saw it land, then they jammed on the brakes, it rocked up and down a couple of times and fell flat, just where you see it.

Anybody hurt?

Naw, they got out, but they were screaming at each other, like they were ready to fight, he said. I drove them in to the office, but the woman instructor was doing most of the hollering on the way in. If I told you once, I told you a million times about that. And now youve busted up the airplane! She just kept that up. I didnt hear the rest of it. I had to get a couple of fire extinguishers out there.

Mike waved and drove on his rounds.

I looked around in the cockpit with my flashlight. The landing gear selector, on the right side of the throttle quadrant with a small, thin plastic disc attached to it, was in the halfway up/down position. The flap switch, to the left of the throttle quadrant was full down.

Outside the props were mangled, the engines were in sudden stoppage damage condition. The fuselage was bent or twisted some way because the cabin door wouldnt close. Underneath, the belly was ground away, along with the flaps, tires, gear doors and antennas. Big bucks for repairs.

I now had something about the people, parts and position of the accident, but lacked information on the paper. I didnt know which ADs had been accomplished, or how much of the airplanes history was on record. The mystery was still a mystery.

Next morning, after the Travelair had been jacked up and the gear recycled down and locked, the bird was towed into the hangar. A mechanic told me that the insurance people had already been out and paid the airplane off as totaled.

What caused the problem, a new multi instructor? I asked.

No, I think they had been training in a Piper Seneca at another FBO, and it went in for engine change. So, the instructor decided they could finish up here in the Travelair, the IA said.

Backwards gear and flap switches.

Thats it, Im sure. They say it just collapsed, and thats what everyone generally tells me, after the accident. I dont know what they tell the FAA. NTSB doesnt look at em any more unless there are injuries.

As far as I was concerned, the mystery had come full circle. The solution was at hand. Well, not entirely. With a qualified instructor aboard, how does a mistake like this happen?

High-Stakes Game
Any event or distraction that can cause a pilot to drop his routine way of doing things in the cockpit can cause a gear-up landing. An electrical loss at the point when the gear is extended, carrying the warning lights with it, will do just fine. Even with all the landing gear lights working, checklists read out faithfully and warning horns blaring, somehow the gear-up landings continue.

The National Transportation Safety Board has studied gear-up landings extensively. There are very few cases on record where death or serious injury was caused by a gear-up landing. The immediate result is an embarrassed pilot, who drops down a few notches from his otherwise good safety record.

Landing with the wheels tucked away is an expensive experience, for certain. By the time you write off the props and gear doors, tear down or overhaul the engines, and replace any antennas that were ground away, the cost can be a substantial portion of the airplanes value. The bends and twists in the airframe and engine mounts are other high-value areas to consider.

Finally, there is the fact that the FAA rarely looks the other way on this type of accident. The pilot may have to prove hes competent to hold his certificate and/or his license may be suspended for 30 days or more. The catch-all careless and reckless operation is cited, and the NTSB is likely to be in full agreement with the enforcement action.

Any event or distraction that can cause a pilot to interrupt the cockpit routine can cause a gear-up landing. Sometimes its an emergency, or potential emergency. Even a go-around, particularly at night, can cause a pilot to skip over the correct sequence of the checklist. An electrical problem at the point when the gear is extended, carrying the warning lights with it, can do it, too. Yes, there are safeguards such as GUMP checks, warning systems and even the feel of the gear extending under your feet. But its not enough.

Going through the NTSB accident reports shows that most can be traced to a small number of primary causes:

Distractions
A good professional CFI (and all Designated Pilot Examiners) usually carries a bag of distractions with them. And its not just to make your ride more miserable. The hope is that the idea will transfer over to the student that there are going to be lots of distractions over the course of a flying career.

You will have passengers who all want your attention at once. One or more will get airsick or become alarmed at some movement of the airplane. This mostly always occurs in the middle of a check list, or just as fuel tanks need changing, or when you get to the undercarriage part of the GUMP checklist.

The approach and landing phases of the flight are critical times, and if a pilots routine is changed, the standard procedure becomes anything but. Lets say you are at the place where we would normally put the gear down, but youre at an airport that is new to you. Youre not sure how far these controllers will send you on base and final, and youre checking out the airport configuration so you dont get lost once you land. Add in a few calls to watch out for traffic, and it may happen that landing gear doesnt get down.

Heres one of the most common scenarios: You are on short final and configured for landing (especially at night) and departing traffic turns onto the runway or the tower requests you go-around. You add power, pitch up, retract the gear and configure the airplane for another round in the pattern. Like countless others before you, you may turn to an abbreviated downwind, base and final. You distinctly remember performing your GUMP check. You know the gear is down.

There is the sound of grinding metal, as you gently touch down, with the landing gear neatly tucked away in its recesses. Sometimes the landing gear warning horn is making so much noise that the pilot cant hear the tower tell him that his gear is not extended, but not often. If there is distraction, pay special attention to your checklist to make sure you have everything accomplished. Distractions are second (or third) priority.

The Abbreviated Checklist
Its very common to mechanically run through the items on a checklist without actually making sure they are accomplished. It can also lead to trouble. Never assume anything.

The checklist is to check off the condition of the items on it. This can easily get derailed with the mnemonics, say the GUMP check. You need to touch the control or look at the gas, undercarriage, mixture and prop as you recite it. When you touch the item, verify that its in the correct position.

This sounds obvious, but its surprising how little thought you can give to something youve done hundreds of times before. Four years ago at Intercontinental Airport in Houston, a DC-9 slid on its belly 7,000 feet before stopping. Minor injuries and substantial damage resulted. The DC-9 had made a look see approach to decision height, when suddenly the runway was visible.

The before landing checklist had not been completed, since a go-around was most likely. Then the decision to land was made. Gear and flaps were deployed, but in the haste to get down to the runway, the checklist wasnt completed and the high pressure hydraulic system didnt get activated. Without the high pressure hydraulic system, the gear and flaps would not extend. A lot of screeching noise followed touchdown.

Excess Stress
A little bit of stress can be a good thing by making you more alert and enhancing your ability to concentrate. But there is definitely a problem with too much of a good thing. If too much stress adds up, you will work at a reduced performance level. No question about it.

If the pilot brings worries about money, marriage and job status into the air, it will have an effect on that pilots flying performance, and the effect can be extreme. Once in the air, there is enough stress to go around, generated by problems with aircraft systems, traffic control, turbulence, vibration, IFR or night operation, and noise.

When stress builds up, you naturally try to shed some of it by developing a kind of tunnel vision in which you concentrate on only a very narrow range of things. Often the concentration will be on things that have no bearing on the safe operation of the airplane. Focusing on something unimportant to the flight can, and does, result in sub-par performance, and that can mean failure to extend the gear before landing.

Another problem, sleep deprivation, seems to be curse of what one scientist has called the 24-hour society. People who should be getting 7 to 8 hours of sleep per day are trying to make do on 3 to 5 hours or less.

Fatigue causes a narrowing of attention – focusing in one direction and neglecting an important task in another. This is seen in auto accidents, errors in scientific work and in dozens of other fields – including operating aircraft. Forgetting to extend the landing gear is a good example.

Risk Management
In the dear, gone days of yore, there were fighter pilots who put the landing gear switch in the UP position, while they were on the takeoff roll. The gear wouldnt fold on them as long as they had weight on the wheels. A squat switch located on the landing gear strut protected the system.

The instant the weight was off the wheels on liftoff, the micro switch was activated and the landing gear retracted automatically. Cool. Well, most of the time.

If they hit a bump or an unlucky upward lifting wind gust, the airplane would be lifted up high enough to activate the squat switch and the gear would fold as it was supposed to. If the plane wasnt quite ready to fly, the flight ended in one of those screeching slides.

Now and then people still try that. Now and then they come to a quick stop.

Another trick is employed by pilots who are in such a hurry to raise the gear that they hit the switch before theyre even out of ground effect. This may look neat to spectators on the ground, but it may result in settling back on the runway without the gear. If you use takeoff flaps, certainly dont be in hurry to raise them until you have lifted clear of the runway. You can still settle gently back on the runway. Without the landing gear, that will be a full-stop landing.

If you should have an engine or fuel problem on takeoff and still have runway ahead, having the gear down and locked could make the problem far less expensive to repair.

Touch and go landings in a retractable gear airplane have a risk attached. On the go, the power comes up and flaps go to takeoff position. Instructors need to stay on top of this one. The pilot may reach for (and activate) the wrong switch or lever. If the wrong switch was the landing gear and the aircraft has reached liftoff speed or is bouncing, count on the gear retracting.

In many ways, touch and go landings have some real shortcomings as a training device. Sure you get in more landings per hour of practice, but you can also build up some bad habits. A full-stop landing will either get you what you want or you go-around. Short field or rough field practice landings make no sense at all if theyre coupled with a touch and go departure.

In any case, getting in the habit of bringing up flaps while rolling down the runway will result in a habit thats hard to break. And sooner, or later, while still on the runway, the old habit will re-establish itself and the gear could come up by mistake. The problem is that you have reached for the wrong switch.

The wrong switch club has most of its members in some of the earlier model Beech Bonanzas and Barons. The early Piper Aztecs and Apaches had the same control configurations: The flaps were located to the left of the throttle quadrant and the landing gear selector was to the right, which is just the opposite of what most airplanes use. Changing between late and early models, or switching to other twins from Cessnas, causes the kind of confusion that makes gear-up accidents somewhat more likely.

Single-engine Pipers such as the Arrow, Saratoga and Lance, and all Mooneys old and new, have very good records of avoiding gear-up landings. The Piper automatic extension system is a simple concept. If the pilot slows the airplane down below a measured speed, a sensing unit triggers the automatic gear extension system.

The system was ordered removed (briefly) several years ago under the concern that the gear would drop after an engine problem, severely reducing glide range. It can also be an annoyance when practicing slow flight or stalls to have the gear plunk down whether you want it or not.

Another factor working in favor of Pipers is the floor-mounted Johnson bar flap control. Because it is not just another switch on the panel, it is tough to mistake the flap handle for the gear switch.

In Mooneys, the relative lack of gear-up landings is easy to explain. The flaps are not very effective at slowing down the slick airframes, and the drag from the gear is pretty much all that prevents the airplanes from blazing down final at cruise speed.

I have seen several airplanes saved by thinking pilots who inadvertently put the landing gear switch in the UP position on the ground. They simply rolled to a stop without brakes. Next, they got maintenance to put jacks under the wings, so that the gear could be recycled and extended to a locked position.

Better Habits
The best method I have found to prevent gear-up landings is to develop a strong, overriding habit. Its quite simple, but it needs to be practiced and verbally called off, and the pilot must be diligent to never let distractions interfere with it.

When I enter the terminal area of an airfield – about 10 miles out – I reduce power to check the operation of the warning horn, then get the landing down gear and locked. Then I check the landing gear position when crossing the inner boundary of the airport, regardless of whether Im VFR or IFR.

Whether Im teaching or doing the approach for myself, I do my final landing check at the IAF. However, then I faithfully do the gear check at the IFR boundary, the FAF. I also reduce power one last time, once the gear is down and indicates locked, to check the warning horn. Do it enough and the habit will get so ingrained that you wont need to worry about forgetting.

Military services use the ground-controlled radar approach system, and during the approach the controller asks on downwind, base and final approach if the landing gear is down and indicating locked. The military has very few gear-up accidents that are caused by pilot error.

One of the most treacherous situations happens on the night go-around. Usually it is tighter than a normal pattern, and radio calls may interfere on downwind, base and final. The tower cant see your wheels situation. If you had your ingrained field boundary, gear down habit working, you would have had the gear down, as you turned downwind – modified, shortened, or otherwise.

Work on this habit. You wont regret it.


Also With This Article
Click here to view “Human Factors Engineering.”

-by Raymond Leis

Raymond Leis is a CFII and ATP with more than 23,000 hours.

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