by Joseph E. (Jeb) Burnside
Youve heard the old joke before: There are two kinds of pilots-those who have landed gear up and those who will. Its based on the distinct possibility that youll forget to put down the landing gear at some point, perhaps because of a distraction, an emergency or plain, simple forgetfulness.
Trying to prevent a gear-up landing is why we have checklists, mnemonics (GUMP) and gear-warning horns, to name a few preventive measures. And no ones immune-even crews flying large transports have come close to forgetting to put down the rollers. But what about when the landing gear wont come down at all? Or, maybe one leg is hung up while the other two are down and locked. What will you do then?
Anyone flying a retractable should know their specific airplanes landing gear system and its emergency extension procedures. The basics are covered in the Pilots Operating Handbook (POH) or the Airplane Flight Manual (AFM) in the section describing the planes systems. Some systems are stone simple, using a manual lever and mechanical linkages. Others are more complicated, with electric motors, gearboxes, hydraulic pumps and other components. Each of these assemblies and their various parts represent different failure modes that, on a bad day, can prevent the landing gear from fully extending and locking into place.
Just as there are different systems, there are different emergency extension methods. Some use a pump; some use a crank; some require the pilot to release the hydraulic pressure keeping the gear from extending. Almost all of these methods are designed to deal with a specific set of failure modes, however. For example, the Bonanza/Baron series employ a crank mounted behind the pilots seat for manual extension. This emergency system presumes that the airplanes landing gear motor isnt turning, perhaps due to a total electrical failure, and the rest of the system is fine. But the gearboxes in these airplanes can fail, preventing the pilot from cranking the gear down.
In single-engine retractable Cessnas, the system depends on hydraulic fluid to lower the gear into position; more than one pilot has had a passenger open the reservoir to replenish it with whatever liquids they could find, including that mornings cup of coffee.
Regardless of the reason the landing gear wont come down, youre now faced with a bona fide emergency. Even though a landing gear extension failure is an emergency, its one from which you have every likelihood of walking away. In fact, you probably will have a perfectly good airplane, one you can safely fly right down to the runway. The only real issue youll be facing is that you wont be able to use the airplane again immediately after the landing.
Once youve discovered that the gear wont lock into place using the normal procedure, the first thing to do is run the emergency landing gear extension checklist. Its in the section of your POH/AFM covering emergencies. You may have other complications-an electrical failure, for example-that occupy your attention. Tough. You still have to fly the airplane and deal with the consequences of the failure. For example, if its a dark and stormy night and youve lost all your electrics, you have a whole different set of problems than just some wheels that wont roll. On a soft, warm summer afternoon with clear skies, that electrical failure is little more than a minor annoyance. Dont let it divert your attention from the task at hand: Flying the airplane to a landing from which you can walk away.
Acceptance
Okay-youve run the emergency checklist procedure. It didnt help. One or more legs of the landing gear are still not down and locked. Maybe theyre still in the wells; maybe two are down, one is up. Maybe theyre all flapping around in the breeze, somewhere between up and down.
The first thing to do in this event is to accept the inevitable: Youre going to make a gear-up landing. On purpose. At this point, the airplane no longer belongs to you, your buddy or the FBO; its the insurance companys property. Your new job is to deliver it to them in one piece, get out and walk away. Theyll be out the price of some sheet metal or fiberglass repair, some new antennas, a new prop, tearing down the engine and putting it all back together. Double the prop and engine expenses for twins. The airplane will be down a couple of months while all the parts are located and the airframe is repaired and painted. Once the engine is rebuilt, probably with a new crankshaft, itll be installed, a different prop hung on it and the insurance company will write a nice fat check.
Put another way, once youve troubleshot the problem and run through the emergency checklist, theres little else you can do to get the gear down. Instead, a technician will discover the problem and repair it once the airplane is on jacks in a hangar somewhere. Itll probably be something simple and cheap to have fixed on the ground, on wheels. Thats no longer an option now, however. Accept it and move on in your thought process. Youve got one more landing in this airplane. Its going to be one of the best landings youve ever made.
Hard or Soft?
Youll be going through a lot of decisions as you set up this landing. One of them is where to put the airplane, on a paved runway or in the grass next to it. Theres really no debate: Land on the paved runway. Pilots faced with the same decision have been known to land beside a paved runway, thinking that doing so will cause less damage to the airplane and be safer for them and their passengers. It doesnt work that way.
The paved runway is smooth, flat, easy to see and easy to find. Its plenty long enough for your airplane (you were planning to land there with the wheels down anyway, right?). Besides, youre much more used to landing this airplane on a runway, anyway, instead of grass.
Why not land on the grass? Well, for one thing, its not as smooth as the pavement. Unless youve picked a golf course, the grass next to a runway will be uneven, possibly with drainage ditches or culverts, rocks and other obstacles. These will be hard to see and impossible to avoid.
Another problem with turf and grass is, well, the turf and grass. Once the plane is on the ground and sliding, it can dig into the turf, decelerating much too quickly, possibly even flipping over onto its back. Thats not likely to happen on a paved runway. Also, directional control is less certain on grass. Its not assured on smooth pavement, either, but the chances are greater that uneven grass patches or hidden obstacles will divert the sliding airplane from a straight-ahead path.
Finally, a paved runway offers relatively well-known characteristics. The grass may be soggy with rain or standing water. Again, the softer the ground, the greater will be the chance that the airplane can dig into it, possibly coming to an abrupt stop. Last time we checked, there were very few airplanes with airbags installed in their yokes. Sure, that new shoulder harness is supposed to keep you out of the panel at up to 16 G-but how many Gs of deceleration can the seat itself withstand?
The bottom line is that landing gear-up on grass simply presents too many variables that just arent issues when landing gear-up on smooth pavement. Dont even think about a gravel strip or ditching in water; both present their own much-more-difficult challenges than even grass. Go for the paved runway.
Two Down, One to Go
Perhaps the most dangerous scenario involving a malfunctioning landing gear is when two legs are down, but one is not. This is less of a challenge when its the nosegear; much more of one when its a main gear leg that wont come down. In this situation, try to get the gear back up in their wells and land with all of them retracted.
If youve got one main gear down and one up, the airplane will eventually settle onto a wing instead of slide on its belly. Dragging a wingtip is a great way to lose directional control on the runway, allowing the airplane to veer off the runway into the weeds. Those weeds have all sorts of obstacles in them, like runway lights and rocks, and can ruin your well-planned approach and landing. Additionally, youre almost guaranteed to damage the airplane more than if all the wheels were up. With all the wheels in their wells, youll be sliding on the belly; the wings will likely not be damaged at all. By dragging a wingtip, you place unknown stress-for which its not designed-on the wing spar and other components, like wing-to-fuselage attachment fittings. Another risk is breaching a fuel tank-especially a tip tank-and creating a fire hazard. Best to land with both mains folded, if you can.
A hung nosegear presents a different challenge. By landing on the mains and letting the nose settle, youve saved most of the fuselage. The prop and engine will be damaged in a single; the engines and props may survive in a twin, especially if the props are of the two-blade variety. Regardless, the nose and nosegear are going to be wiped out. Depending on the force with which they hit the pavement (You are going to land on the paved runway, right?), the damage could be minimal or it could deform a bulkhead and make repairs uneconomical. In any event, the challenge will be to gently lower the nose to the ground early enough in the landing roll that you still have elevator authority but not so early that the airplane ends up spending most of the rollout on its nose. Remember, too, that what little directional control youll have without a nosegear will come from the rudder and the individual brakes on the main wheels.
At the end of the day, landing without a nosegear makes the whole procedure slightly dicier than landing on the belly.
Final Checks
Make sure the control tower, Unicom operator and other traffic know whats going on. You may want to orbit somewhere, perhaps over the same patch of ground you used to troubleshoot the problem, until the emergency equipment is in place and you can use the runway without potential conflict. After all, your airplane is likely to be on it longer than normal.
Like any other emergency landing, youll want to brief passengers well before the final approach. Make sure they cinch their belts and harnesses tight. Do the same with yours. Also, make sure your passengers know how to get out of their belts and harnesses and exit the airplane as quickly as possible. Using any available pillows to cushion their heads wont hurt, but if you do this right, there wont be any sudden deceleration. Pop the doors and let them trail open so that any cabin deformation wont keep them closed.
In a high-wing airplane, using flaps as you would in a normal landing is a no-brainer. In a low-wing airplane, you may want to leave them up to minimize flap damage. Its a toss-up: Flaps are relatively cheap to replace, even if they get damaged. On the other hand, if youre not familiar with or havent done a flaps-up landing in a while-itll be more difficult to get the nose up into a flare and the stalling speed will be higher-add full flaps when the runway is made as you normally would. Again, they belong to the insurance company now.
Keep the engine running into the landing flare. In the flare, turn the fuel selector to the OFF position, kill the master switch and ride it out. Early in the slide, you can use the rudder for some measure of directional control but that will be out of your hands sooner rather than later. The best you can hope for is to be on the centerline when you touch down and when you lose rudder effectiveness. Once the plane comes to a rest, get out and away from it.
Once youve caught your breath, whip out your cellphone and call your insurance company. Tell them about the great deal they just got on a slightly used airplane.
Also With This Article
“Stupid Landing Gear Tricks”
“Stop the Prop?”
“Intentional Gear-up Landings”
