M20R Gear problem

[Fritz Kaiser]

Hello Sirs,

todays flight, short after take off ..we habe a positive rate of climb and I actuated the gear swtich .... and the gear just goes 70% in !

I lowered the gear the gear was down and safe!

second attempt.. the same...just about 70% in.

I lowered the gear  ... "three greens"

Third attempt the same ...... i lowered the gear and landed safely.

immediately after stopping the engine I removed the belly  ....everything looks fine.  all gear switches are looked at there position.

all Gear doors looking like they should look. 

on Monday i plan to fly to my maintenance facility with the gear down all the way.

any mooneydriver had the same problem here.

Thanks in advance

Fritz

 

[rgpilot]

Only problem I've had with the gear was after service. The mechanic must have kicked the manual retraction lever. Reset lever and problem solved. This is always the first place to look in a Mooney,

 

[carusoam]

Fritz,

What were the signs of the abnormal gear retraction?

How did you know/estimate(?) of the 70% retraction?

 

Additional thoughts...

1) Interference with the manual gear extension system is the usual culprit for gear issues.

2) Makes one of Oscar's belly cameras sound like a good idea.  

3) Any tire changes lately?  Air pressure / signs of binding in the wells?

PP thoughts only.  Not a mechanic.

Best regards,

-a-

[BillC]

Haven't had the problem in my Ovation but please post the outcome so we can all learn from your experience.

[Guitarmaster]

Airspeed/Squat Switch issues?

Sent from my XT1254 using Tapatalk

[Guest]

Up on jacks is the place to diagnose this problem.  You were flirting with disaster on your second and third attempts to raise the gear.

Clarence

[Fritz Kaiser]

Hello ,

yesterday i flew to my maintenance shop ( all the way gear down !)

We put the Mooney on jacks an cycled the gear .... no malfunction.. we did it about 10 times!

Everything looks pretty good. 

Than I tried an other time to  retract the gear and i forgott to push the red buttom above the gear swtich and the gear went in!

They told me that I need a new  air switch, who is located behind the airspeed inicator.

Could this the reason for the gear retract malfunction ?

What do you thing about that?

Greetings

 

Fritz

 

[carusoam]

From what I thought I knew...

1) The air speed switch needs to sense the airspeed to start the retraction.

2) The bypass button can be used when the airspeed switch doesn't work.

3) is it possible that the switches need to held closed during the retraction process?

4) either way, it shouldn't retract on Jack stands without the airspeed or by-pass switch

5) sounds like the airspeed switch is both sticking open and sticking closed at different times...(?)

6) if the by-pass switch is a temporary close, only when activated... does it operate a relay somewhere else?  If it uses a relay, that may be the issue...  there are a handful of relays that need to be kept clean in the landing gear system...

Best regards,

-a-

 

[kortopates]

1 hour ago, Fritz Kaiser said:

Than I tried an other time to  retract the gear and i forgott to push the red buttom above the gear swtich and the gear went in!

Obviously that's not right. On jacks, after putting the gear switch to the up position, the red bypass light should have illuminated first indicating you need to push and hold the bypass button to raise the gear. Is it the air speed switch or wiring? One will need to trace the circuit to determine where the fault is.

[carusoam]

Great details, Paul!

Best regards,

-a-

[StevenL757]

Fritz,

Agree with Andrew in that verifying the physical condition of your gear is acceptable prior to launching.  You have a couple of different issues going on if I've read correctly.

First, as mentioned, with the plane on the ground, when you select gear up, the gear should not retract.  Blowing air into your pitot tube (to produce ~50 knots or greater) should retract it normally.  Unless your airspeed safety switch is stuck in the open position, this would not have caused your original retract problem.  Unless your mechanic has already done this, check to see if the switch isn't sticky.  We check it every annual, and they do prove to stick somewhat frequently.  New switches are available from Mooney for about $750USD and are generally good for between 6 and 9 years.  Used ones are available, but their lifecycle is ~3 years, hence not recommended.  Depending on how crowded it is behind your original panel (1995, I believe), your mechanic should charge 2 to 3 hours to change it out.  It's on the left-hand side of the skin about 10 inches behind the panel on a bracket near the A/S indicator (as you mentioned).  Your replacement part number will be Mooney Part# 880013-507

Your issue of the gear not retracting all the way is a separate issue, and could be caused by (among other options I'm sure...) a faulty Up-limit Microswitch or a Gear Relay.

Observations based on experience...let me know if this was valuable.  If you need part numbers for either or both the Up-limit switch or Gear Relay, let me know.

Regards, Steve

[Two Oh One]

On October 20, 2016 at 11:11 AM, StevenL757 said:

Your issue of the gear not retracting all the way is a separate issue, and could be caused by (among other options I'm sure...) a faulty Up-limit Microswitch or a Gear Relay.

I've got to say, reading the original post had me shuddering.  Several mechanics think my gear up landing was caused by a weak up-limit switch allowing my actuator to seize itself in the retracted position.  The only warning I ever got was a strange "Gear Unsafe" light after retraction during my second flight around the patch in my new-to-me bird.  

Like Fritz, I naively dropped the gear and all went well, until it didn't on a subsequent lap.. Glad you had better fortune sir.

[triple8s]

1st thing i would do, very simple, cheap,  probably wont fix it but if it does as i said its cheap. With plane on jacks belly panels off, lay under plane and have someone cycle or attempt to cycle the gear so you may observe the mechanism and also familiarize yourself with what is going to move and where it is going to move. Next step turn the lights down. You may need to turn off the main lights and get a small light. You want just enough light so as to keep from putting fingers where they can get into trouble. Next step, gently jiggle the gear wiring looking for any shorts, they will be easy to see with the lights low. Try this with the gear retracted, extended and, the tricky part, while it is operating. I had a gear issue and it was very hard to figure out because it was very occational. The gear would pop the breaker once in a while. My problem was in the wiring. Two conductors had somehow gotten chaffed and would short just once in awhile. 

Good luck