By: Ken VeArd
Flying a complex aircraft with retractable landing gear introduces a whole new level of complexity and things that can go wrong. When you have the slightest hint that there is an issue with the landing gear you should slow down, think, and return for a safe landing as soon as possible. This video shows how I handled a situation when I went to raise the landing gear and it wouldn’t come all the way up.
Recap of the Flight
We took off from 35R at Austin Bergstrom International (KAUS) in a Cessna Cardinal (C177RG). Our planned mission was to fly to Easter Wood (KCLL) where I was going to meet my flight instructor to perform my Flight Review.
After an uneventful run-up, it was time to line up and wait for takeoff. An American MD-80 had just landed in front of me, so my thoughts turned towards wake turbulence avoidance. I noted where the MD-80 touched down and when I received takeoff clearance, I slowly rolled down the runway for a little while before applying full power. This was to ensure I would not be generating any significant lift prior to the MD-80 wake turbulence and would lift off the ground well past where they touched down.
When to bring the gear up?
I see many pilots of complex aircraft raising the gear at different times. Some bring them up immediately after take off, some delay. First check your POH to see if it offers and guidance for raising the gear. As you hear me verbalize in this video when I take off I wait until the following criteria are met before raising the landing gear:
- No usable runway left
- Positive rate of climb
This is important because if you have an engine out right after takeoff and you still have runway in front of you, you will not have time to put the landing gear down. Once you make your first turn or in the event that an engine out would take you past the end of the runway, chances are landing with the gear up will be your best choice. So get that gear swinging as you transition from where you would land on the runway to off field.
First Hint of a Problem
It was my co-pilot who actually saw it first, the gear didn’t go all the way up. In the Cardinal, we have mirrors that allow us to visually see the landing gear. Otherwise it would have taken me a little while longer to realize there was a problem. In the Cardinal we have three lights.
- Green Light to indicate all three landing gear are down and locked
- Yellow Light to indicate all three landing gear are up
- Red Light telling me if the landing gear motor is running or not
Normally from the time you raise the gear it takes 10-12 seconds for the gear to fully transition. The sequence is: green light goes off, red light turns on and then you wait. Then yellow light turns on and red light turns off.
In this case the gear went halfway up and the red light turned off and the yellow light turned off as well. This is a very odd presentation of information. The gear motor should run until the sequence completes with the gear up yellow light turning on. Something must be telling the motor to stop.
First troubleshooting step was to lower the gear again. The gear motor turned on and the gear went down and I got a green light. Green light made me feel better.
Then I raised the gear again. Same thing, halfway up and then the motor stops. Now I am officially worried that something is wrong with the landing gear system. I put the gear back down and thankfully it goes down and gives me a green light.
Not willing to risk bringing the gear up again for the fear the hydraulic fluid may be leaking and the gear will never come down again… I leave it down. Now it is time to start thinking about returning to home and land.
Rules for retying in aviation
Whether it is landing gear or a circuit breaker, you should establish some rules for how you retry and when you retry. If a circuit breaker pops, wait 2 minutes for it to cool over. Press it in and test. If it pops again… DO NOT PRESS IT BACK IN. It is trying to tell you something. Pressing it back in could result in an electrical fire.
Using the same logic with the landing gear… I tried it again once. I got the same results. Once I saw a green light, troubleshooting was over. Having a green light was a comforting and safe feeling.
Is this an Emergency?
You will hear my transmission to Austin Tower, “We would like to return home, uh… no emergency.” This was because in my previous experience with Austin Tower, if you mention, “Landing Gear Trouble,” they will quickly go into emergency mode and roll the fire trucks and send the airliners away.
In this case my decision point of if I am in an Emergency or not all hinged around the green light. Green light = normal conditions, no green light = send the fire trucks.
When in doubt… Tell the tower or ATC of your situation and declare an emergency. In this case, I didn’t feel it was warranted. But had I told Austin I was having issues and would like an immediate return, I would have also been justified.
The C177RG went in to the A&P shop and the root cause was found. It turns out that one of the micro switches on the down-lock cams needed adjusting. When they put the plane on jacks and swung the gear, everything work well. But shaking the airplane during the transition the A&P was able to reproduce the symptoms. To under stand why this would produce this result you first have to understand the sequence of events that happen when you select “GEAR UP”.
- Actuators pull the down-lock cams allowing the gear to travel. A micro-switch then tells the motor it is time to start running
- The Motor runs pulling the gear up
- The gear triggers a micro-switch when it is in the full up position
Since the switch in step 1 was turning off halfway through the swing, it told the motor that it was time to stop. Knowing this, it turns out the event was not a true safety issue and it was reasonable to expect that the gear would extend either by the electric motor or by manual extension if needed.
Regardless, if you ever have anything out of the normal with the gear… This procedure still stands:
- Put the gear down
- Manual extend if needed
- Get a green light
- Make a safe landing
- Have an A&P inspect and make any required repairs