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Emergency Gear Down Procedure - Practice


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I learned a valuable lesson yesterday and want to pass it along to others. Practice your emergency procedures EXACTLY like you plan to do them in real life. My plane is a 64 M20E with electric gear. At every annual, I practice my “Manual” crank the gear down routine two or three times. I have always been too chicken to actually try it in the air and maybe screw something up resulting in an unnecessary gear up landing. When I practice, during annual on jacks, I'm always worried that I'll forget to pop the circuit breaker (the one down by the crank) and have the system come alive part way down and spin the crank, break my wrist and maybe really screw up the crank system. Well, yesterday I learned several things about my Emergency hand crank gear-down system and my self training. I had a real gear failure.

It started with an alternator failure and a 3 year old battery. I had been out just tooling around the local area at low altitude for about 30 minutes when my alternator failed. My JPI 900 did a wonderful job of getting my attention by blinking “Voltage” and the red warning light on the panel. As soon as I noticed the warning, I saw that my ship voltage was at 11.7 and about every 10 seconds it dropped another 0.1 volts. I was about 10 miles from the airport, so I turned for home, and with the voltage at 11.5 volts, decided I should get the gear down early. Switch down, Amber “up” light goes out and I can feel the gear actuation in my seat, but then it stopped and the Green “gear down” light didn't come on. It REALLY does take some period of time for you to accept the fact that this is for real. I just stared at the panel lights for a while. Then I cycled the gear “Up”, but nothing happened. Then down again, and nothing. By now I was approaching the airport (uncontrolled field), so I turned away from the airport to sort things out. My altitude was only 2500 MSL (1700 AGL), since I had just been out sight seeing.

So here's the lesson I learned. When in the hanger on jacks, in nice lighting and no severe clear sun shinning in on me with the one hour before sunset glare, I could always easily see the circuit breaker and the funny little red “almost a knob” gear engagement lever. It was never a problem to see them or to reach them. Just like the fact that I have one of the famous plastic pipe fuel valve selector tools, because when you are actually flying, you have to be a contortionist to reach the valve selector, so goes the gear circuit breaker and crank engagement knob. I didn't realize until yesterday that every time I practiced, I was not strapped into my seat, and I had the seat pushed back to give me room. A whole different deal for a short guy like me while actually flying the plane. I for the life of me, could not find the circuit breaker with my finger tips. I finally got my flashlight out, and used it so that I could see down there. The sun was so bright outside the cabin, that I simply couldn't see it. Also, it took several tries using my left hand to successfully pull it out. Same went for the Red crank knob. Pulling it out with my left hand was quite difficult. I realized that I had always leaned in from my comfortable position of seat pushed back, and my rear-end scooted over six or 8 inches from the left wall. I had actually been reaching in with my right hand which gave me a much better angle to grab the breaker and the knob, and I am right handed so that helped too. By the time I got the breaker out, and the knob pulled and then pushed forward on the arc, I discovered that the plane had gone from straight and level to a 15 degree right bank, and that I was in a descent and had lost 400 feet. I was now only 1300 AGL.

I returned to the airport and did a 200 foot low pass so the lineman at the FBO could confirm I had 3 wheels down for whatever that is worth.  The green "Down" light did not come on, as it never does even in practice on jacks.  When I disengage the crank, and push in the circuit breaker, the motor runs for a tenth of a second to tighten everything up, and that last 1/16 of an inch makes the down limit switch.  So, I was pretty sure the gear was down, but it was reassuring to hear it from someone who could actually see it, even if it was not "locked down".  I shot one of my best ever landings with a 7kt crosswind gusts to 12. Not skill, just the right gust at the right second before touchdown.

My takeaways and suggestions to others: Practice EXACTLY like you plan to do it. In this case, that means with my seat-belt on tight, and my seat up close exactly the way I fly. Or, plan to move the seat back, and why not use my autopilot with altitude hold?? Never thought of it, because I didn't have a checklist and never practiced doing that. Why did I not climb to 3000 feet then mess with it?? If I want to reach it without seeing it, then practice that, and use the hand you plan to use. Believe me, it makes a real difference.  Kind of like that first car date a million years ago :)

I learned something yesterday that I think will make me a more prepared pilot in the future. Hope this long winded story is helpful to others.

-mark

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I had a total electrical failure just after breakout on a VOR-A approach with my CFII a few years ago. Remember the number of cranks it takes to go all the way down. Mine is 52.

Like yours, mine went partway down, I could only add another 6-8 turns of the handle. But there's that nice, big floor indicator that I always doublecheck on final . . . which is when I remembered to check mine.  :rolleyes:

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10 hours ago, Mark942 said:

why not use my autopilot with altitude hold??

Do you know if your autopilot and altitude hold will work on 11.5 volts?  From my own alternator failure, I know you will stop transmitting on your radio long before you stop receiving.  I should have written down the specific voltage at which that happens, but I think it was around 10.5 volts for my radios.  Also, your transponder is a huge power drain.  I suspect that is also due to the additional power required to transmit, but it is transmitting all the time.  If you need to save battery power for something more critical, sacrifice the transponder.

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39 minutes ago, Hank said:

And (right) shoulder surgery for the lose . . . .

Amen, brother.  Amen.

I would have loved a manual gear 20 years ago when I bought my C, but now I'm so glad my gear is like all the modern Mooneys, electric, but without the no-back spring.

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6 minutes ago, Mooneymite said:

Amen, brother.  Amen.

I would have loved a manual gear 20 years ago when I bought my C, but now I'm so glad my gear is like all the modern Mooneys, electric, but without the no-back spring.

Hmmm . . . We don't have a back spring, and we don't have a no-back spring!  :blink:

No busted knuckles, no loose seatbelts, but still an unhappy right shoulder. Just not as unhappy as it would be if it had to drag the gear up and down!

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2 hours ago, RobertGary1 said:

Something doesn’t sound right. Are you saying that you can’t get the green down light when manually cranking it down during annual??

Seconded.  The POH (for my make and model at least) explicitly says the green light should come on with manual cranking, see below.

It sounds to me like you're not actually cranking the gear into the fully locked position:o  The crank does get harder to turn at the end of the cycle, as the over-center locks are going over-center.  But this is not a bad thing, or a reason to stop cranking - you're supposed to keep going until the green light comes on.  If pushing the breaker in after you stop cranking results in the motor running a little bit and lighting the green light as you describe, it likely means you didn't crank all the way to the locked position in the first place.

Inkedpoh-gear_LI.jpg

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My emer extension will activate the green light. 65E electric gear. Sounds like you just saved yourself from a hull loss by needing to re-rigging the gear. 
I have a lanyard safieted to the collar on the CB to help pull it when needed. I simply could not fly and pull the CB at the same time. The collar helps. 
-Matt

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3 hours ago, Vance Harral said:

Seconded.  The POH (for my make and model at least) explicitly says the green light should come on with manual cranking, see below.

It sounds to me like you're not actually cranking the gear into the fully locked position:o 

I thought the original post was about cranking the gear down during an electrical failure.  Since the green light depends on an electrical system, not having the light would be normal.  As @Hank pointed out, that's why there's a gear down indicator in the floor.  If the green stripes line up, the gear is down, regardless of the light.

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8 hours ago, steingar said:

Johnson bar for the win!

May be I suck at operating Johnson bar, but I was checked out in a Johnson bar Mooney.  The bar popped out of the up right position on final.  The gear safe light was green before that.  That incident convinced me to look for an electric gear Mooney.  All mechanical things fail.   No sense beating up my shoulder and scare the passenger with nose dive at 100 AGL just to retract the gear.  :)

Back to the OP.  Thank you for sharing.  The early Mooney must have been designed by a contortionist.  I can't reach the fuel tank selector without a PVC pipe.  It's pain to try to operate the manual gear down crank with me fully strapped in.  

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4 hours ago, Mooneymite said:

I thought the original post was about cranking the gear down during an electrical failure.  Since the green light depends on an electrical system, not having the light would be normal.  As @Hank pointed out, that's why there's a gear down indicator in the floor.  If the green stripes line up, the gear is down, regardless of the light.

There may be enough electrons in the battery to continue illuminating the light (low amps) even after it can no longer drive the motor (high amps).  But that's beside the point in this particular thread, because the OP said he doesn't turn the crank to the green light even under test conditions on jacks at the annual with a good battery.

The assertion that "if the green strips line up, the gear is down regardless of the light", is an oversimplification - one that assumes perfect rigging of the both the gear system and the indicators.  The strict definition of "gear down and locked" is when the preload torque on the over-center locks is within the tolerances specified in the service manual.  In a perfect world, the green light would illuminate and the floor indicator would exactly align, when the preload torque is precisely in the dead center of its range.  In the real world there can be differences, and it sounds like that's the case in the OP's airplane (and likely all of our airplanes, to some degree).

If you read the service manual for electric gear rigging, preload torque is checked on the basis of the green light, *not* the floor indicator.  This is because the switch that illuminates the green light is part of a two-pole switch, with the other pole being the switch that actually turns off the motor.  Assuming the OP's gear is correctly rigged, it sounds like the floor indicator is slightly "off", such that it appears aligned when the preload torque is a little shy of the recommended range.  It may also be that the floor indicator is good, but the gear is mis-rigged such that it slightly overdrives past the recommended preload torque.

Suggest at the next annual, the OP crank the hand-crank until the floor indicator is aligned but the green light is not on per his usual practice, and check the preload torque there; then continue cranking until the green light is on, and check the preload torque again.  If both values are within the service manual tolerance range, then either indicator is "good enough", despite the fact they're associated with two slightly different preload torques.  If not, then the gear needs to be re-rigged and/or the floor indicator needs to be adjusted.

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6 hours ago, Vance Harral said:

Suggest at the next annual, the OP crank the hand-crank until the floor indicator is aligned but the green light is not on per his usual practice, and check the preload torque there; then continue cranking until the green light is on, and check the preload torque again.  If both values are within the service manual tolerance range, then either indicator is "good enough", despite the fact they're associated with two slightly different preload torques.  If not, then the gear needs to be re-rigged and/or the floor indicator needs to be adjusted.

My floor indicator is painted onto part of the landing gear itself. There is no "adjustment" available . . . .

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3 hours ago, Hank said:

My floor indicator is painted onto part of the landing gear itself. There is no "adjustment" available . . . .

In that case I guess pilots are expected to observe where the lines are when the green light illuminates under normal conditions, and crank to that spot.  Again, in a perfect world, they would be exactly aligned from whatever point of view the pilot has while cranking, at the point where the over-center preload torque is at spec.  I'm sure in most cases it's reasonably close.  If not, it's still unlikely the gear are going to collapse on a normal landing.  It's just not "locked" in accordance with the service manual spec.

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1 hour ago, Vance Harral said:

In that case I guess pilots are expected to observe where the lines are when the green light illuminates under normal conditions, and crank to that spot.  Again, in a perfect world, they would be exactly aligned from whatever point of view the pilot has while cranking, at the point where the over-center preload torque is at spec.  I'm sure in most cases it's reasonably close.  If not, it's still unlikely the gear are going to collapse on a normal landing.  It's just not "locked" in accordance with the service manual spec.

I just cranked as far as my crank went when I had to, then checked the floor. It said "safe," so I landed and called my A&P.

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  • 1 month later...

Hi guys, my original reason for the post was to simply say that even though I practiced emergency manual gear lowering, I didn't even realize that I was "cheating" by scooting to the middle of the right seat, using my right hand to reach down and actually operate the breaker and engagement button slide, and then using my strongest hand/arm to crank the gear.  None of these things can be done while actually flying the plane strapped into the left seat.  Being able to do this in bright sunlight when you can't see down into the dark hole of the area around your knees with a brilliant sun day.   Also, I had no check list to refer to so that I would do simple things like look at the gear indicator in the floorboard to verify that the gear was actually down.  I do that "Every" time on down wind but never thought of it in the heat of the moment.  VERY disappointed with myself.  I did a low level fly by the FBO who used binoculars to "verify" that my gear was down, but a simple look at my floor indicator would have been much more reliable.

My whole point of the post was to say, hey guys, make sure you are practicing your procedures as they will actually be required, and challenge yourself to make sure you are using best practice.  I now have a simple emergency gear down checklist which includes simple things like "Climb" to a safe altitude first, etc.

'

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  • 2 months later...

I climb this post because I had a problem with the crank cover when exercising. I specify that the original cover being very damaged, it had been changed by the model sold by "plane plastic". The following photo shows the crank and circuit breaker space of this new cover, which is not the same as the original, and access to the button is compromised. You suspect the difficulties that this generates in addition to the additional stress. I decided to rebuild the spacing of the "flat plastic" trim to eliminate this defect. Does anyone else know about this kind of problem with the "plane plastic" cover ?

 

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