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On some GA aircraft such as the Piper Malibu, the propeller would touch the ground if the gear was up. How would you land the plane when gear actuators fail?

I would pull out the mixture knob and turn off magnetos, so the propeller is stopped when it touches the ground, but what is the official/best way to do this?

You can assume the propeller is constant-speed.

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    $\begingroup$ Unless you have a very long runway that you can cut the engine with plenty of altitude, yet still over the runway and still land and come to a stop on said runway, forget the engine/prop, put the aircraft on the centerline at the intended touchdown spot. You're in an emergency, you need to focus on flying the airplane not saving the engine or prop. You don't win by saving the engine while crashing short of or to the side of the runway. $\endgroup$ – falstro Sep 13 '14 at 14:06
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    $\begingroup$ @Farhan I removed the "avoid propeller damage" part in the title. I'd think propeller damage is just one of the concerns (the hazards caused by striking a propeller to the ground is another). $\endgroup$ – kevin Mar 22 '15 at 9:22
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    $\begingroup$ Well, you certainly aren't going to be able to go around once you touchdown. $\endgroup$ – Rhino Driver Mar 23 '15 at 5:02
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Not only some, but in fact most GA propeller-driven aircraft have propellers that extend below the bottom of the fuselage. (The only exception that quickly comes to mind is the Cessna Skymaster; I'm sure there are plenty of others.)

Note that the aircraft will have some secondary method of gear extension, such as gravity drop, a manual crank, or a blow-down bottle. But there are still times where the gear cannot be extended and locked.

In this situation, you've got one emergency. Don't make it two emergencies by shutting down your engine. There's an aphorism - "If the gear fails, the insurance company just bought the airplane."1 Without gear, you're going to do some damage: scraped belly, probably tearing off some antennas. The aircraft will already require maintenance; the extra time and cost of an engine teardown is insignificant compared to the increased risk from a higher workload and a landing that the pilot may not have ever practiced before. (The approach with gear up and engine out will be different than that with gear down and engine at idle in a simulated engine failure.) Don't risk your life to save the insurance company money.

Additionally, just stopping the engine isn't sufficient to prevent a teardown. You must also rotate the prop so that it's horizontal, which requires slowing substantially as you pull the mixture to stop it from windmilling, and then using the starter to move the prop.2 You'd need to prevent any substantial contact between the propeller and runway, as Lycoming's Service Bulletin on propstrikes that require inspection and repair (Continental's is similar) includes the situation of

Any incident, whether or not the engine is operating, where repair of the propeller is necessary

After all of that, there are some best practices:

  • Declare an emergency. ATC will help you, have equipment ready on the ground, and clear traffic around you - but they need to know about it first.
  • Use your checklist. An airplane with retractable gear will have an entry for gear failure; follow it. In particular, you'll shut down the electrical system before landing, and probably brace open a door for exit.
  • Land on a paved surface. Dirt or grass may seem softer, but they aren't as smooth. According to an AOPA flight-training newsletter, "Statistics suggest that putting the airplane on the asphalt is likely to cause less damage to you and your airplane than putting it on the grass."

(1) I've also heard "The insurance company buys the aircraft when you take off; when you land safely, you buy it back."

(2) Or you could do it in the flare - a suggestion so dangerous I include it only for completeness.

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  • $\begingroup$ I completely agree with @NathanG's advice, shutting your engine down makes a bad situation worse and limits your options. It also upsets attitude and trim, creating distractions when you least need them! $\endgroup$ – GdD Sep 15 '14 at 12:29
  • $\begingroup$ I can't stress how important it is to remove all power sources in the cockpit when you make a gear up landing. A powered engine with fuel flowing the pipes spinning the empty propeller shaft while you slide down the runway with the belly of the aircraft? $\endgroup$ – kevin Sep 15 '14 at 12:43
  • $\begingroup$ @GdD: if its' limiting your options, then you're cutting the engine too early. $\endgroup$ – kevin Sep 15 '14 at 12:56
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    $\begingroup$ You're about 20 feet above the runway when you do that. Yea a rabbit can suddenly jump onto the runway too. But why? I've known people who died due to post-crash fire. I've also seen other pilots cut the master then survive. My choice? By 20 feet, I'm committed to land. I'd rather risk skiing to the grass due to crosswind than a post-crash fire. $\endgroup$ – kevin Sep 15 '14 at 14:59
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    $\begingroup$ @kevin I wonder how much fire risk is actually reduced by turning off the power. I would think that much more of the ignition risk comes from a piece of aluminum scraping across a piece of asphalt at 100 mph than from the engine running. $\endgroup$ – reirab May 5 '15 at 15:47
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Don't shut down your engine, it's a bad idea. Your aircraft will require substantial repairs in any case, the most important thing is to land safely. Loss of engine power is a serious emergency, worse than landing gear not lowering, cutting your engine is multiplying the risk several times over. Survival in this case depends on a smooth, controlled landing; cutting the engine causes risks to this:

  1. Higher descent rate: most aircraft have a higher descent rate without engine power than at idle, sometimes this is substantial. A higher descent rate is not good when the smoothness of your landing is critical
  2. No control over descent rate: without your engine you cannot add a burst of power to smooth out a sudden drop. This could lead to you slamming down on your belly instead of having a controlled landing. It could also lead to landing short of the runway if you cut it too soon. This has happened several times, and often is not survivable
  3. Inexperience with dead stick landings: Few people have ever experienced how an aircraft without power handles and lands, you'll be entering new territory for which you've had no training
  4. Less control without the engine: Airflow (at least in single engines) contributes to elevator and rudder authority, even when at idle, you need all the authority you can get for the most controlled landing possible. Also, you can use your prop to keep you in place in a crosswind
  5. No option to go around: once you cut your engine you are committed and have no option but to land, what if a big gust blasts you off centerline and into the path of a hangar? Or what if you aren't perfect and want to have another try?
  6. Change of attitude and balance: Cutting the engine will give some pitch down on most aircraft which would need to be controlled for, but you've cut your master switch so your electric trim is out - better start winding that lever or have the arms of a gorilla
  7. Distraction at a critical time: Landing is one of the busiest times in an aircraft, you have to watch your airspeed, descent rate, and if it's bumpy you'll be sawing away at the controls. Having to pull the mixture - bump the prop to it's horizontal (no point cutting the engine otherwise) - cut the mags - fuel stopcock off - master switch off all while arresting an increased sink rate, trimming, and coming to terms with all the balance changes will all add massively to your workload when you most need to be concentrating on making a controlled, gentle descent.

A good landing comes from a good approach, cutting your engine throws that away, and you cannot go around if you hose it up or conditions aren't right. Instead make a controlled approach, brief your passengers on emergency procedures, tell them to brace. When your airplane comes into contact with the ground use whatever control authority you have to keep it controlled, then once it is slowed cut your fuel, mags, etc. As Bob Hoover said "fly it as far into the accident as possible."

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Your instinctive actions are correct; killing the engine is the correct way to handle this emergency.

Here's part of the (generalized) procedure for landing a propeller aircraft with the gear up:

  1. Pull the circuit breaker to the gear. We don't need the gear suddenly popping down and surprise us. Once you've made up the mind that the gear won't go down, stick to that decision.
  2. On short final, door latch open. The last thing you want is trapped in a smoking or burning aircraft.
  3. On crossing runway threshold, mixture cutoff, ignitions off, master switch off
  4. Flare as much as possible and aim to hit the ground at a slower speed
  5. Expect smoke to fill the cabin due to heat caused by friction, or even a fire
  6. If you have access to a fire extinguisher while inside, extinguish cabin fires only if absolutely necessary.
  7. Get out of the aircraft ASAP.

Unless the aircraft has props hoisted on high wings, it's almost certain that the prop will hit the ground and smash. Even if the prop is not rotating as it hits the ground, it'll still be chopped off. The reason to turn everything off is to minimize potential sparks, fire and explosion as much as possible. Also expect extensive damage to the aircraft.

Obviously you'd want pretty little red lights standing by as you make the approach.

As for other comments saying you should not turn off the engine, obviously no sane pilot will do this while at 5000ft and 13mn from the airport, right?

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  • $\begingroup$ Metal propellers are made of aluminum, so they will not spark. Also, if you decide to land gear up in something like a Malibu with gravity extend gear, pulling the breaker will cause the gear to extend. $\endgroup$ – NathanG Sep 13 '14 at 21:55
  • $\begingroup$ The ignition systems of the engine spark during operation. Not to mention the chance of a fuel tank rupture is very real. There is no guarantee that the gear will extend - the assumption here is that we have done everything and it just won't come down. $\endgroup$ – kevin Sep 14 '14 at 6:26
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    $\begingroup$ This is very wrong! There is no recommended practice to cut off your mixture and shut down the engine - you are simply adding one emergency to another and giving yourself no option other than land. People have died following this advice! $\endgroup$ – GdD Sep 15 '14 at 12:26
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    $\begingroup$ Nope, not cutting it is very wrong! Passengers have perished in the resulting fire when a twin prop made a powered gear up landing in the field. If you don't do it you're simply inviting disaster. In fact it's a standard practice of any crash landing. $\endgroup$ – kevin Sep 15 '14 at 12:35
  • $\begingroup$ exactly like this. $\endgroup$ – Erich Mar 24 '15 at 14:22
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(I will note that I am NOT a pilot, only an enthusiast.)

Kevin's answer appears to be the most correct one, without giving the actual CORRECT answer. The only correct answer is to perform whatever emergency procedures are contained within the POH, or Pilot's Operating Handbook for the aircraft you are flying, coupled with any revisions, etc.

(Please note, the following links are to scanned in copies of the POH's, and are not links to the manufacturers websites, but to private companies)

I did some quick research, and three aircraft, specifically the Piper Arrow PA-28R-201, the Cessna 210M Centurion, and the Cessna 421C Golden Eagle, all have emergency gear up procedures. In all three cases the procedure includes ignition off, magneto's off and fuel off.

There may very well be an aircraft whose POH indicates full power and fuel during emergency gear up landings. However, the only way for that to be the correct procedure is for some documentation to say it is.

Also, no where am I suggesting that during an emergency you pull out the POH and read it. Very contrary, I am suggesting that you read and re-read the applicable documentation for the aircraft you are flying at the moment until you are very familiar with it.

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    $\begingroup$ I agree that following the POH is the correct procedure. However, the Cessna documents call for (1) master off; (2) touchdown; (3) mixture/mags/fuel off - in that order. The Arrow does not have a gear-up landing procedure; it does discuss landing gear-up and call for electrical and fuel shutoff before touchdown - but only in the checklist where the engine has already failed. $\endgroup$ – NathanG Mar 22 '15 at 15:58

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