BE-76 Squat Switch Question

[Fearless Tower]

Currently studying up for my Commercial and seem to have found a point of confusion WRT the landing gear on the Duchess.

The POH clearly states that the inadvertant gear retraction safety feature is a pressure switch within the pitot system that de-activates the hydraulic pump whenever pitot impact pressure is less than 59 kts.

Now, every Duchess that I have seen has squat switches, but I cannot find any reference to the squat switches in the POH.

Can anyone shed any light on this? Do the squat switches on the Duchess work the same way they do on other retracts, or do they have a different function?

I did find an interesting Caution note in the Handling Service and Maintenance section that states you should pull the landing gear CB and open the emergency extension valve when jacking the plane up. Seems those precautions would apply if the squat-switch worked the way I suspect it does, but doesn't make a whole lot of sense if the safety device is pitot impact pressure.

Thanks,
Andrew

 

[Areeda]

It's been a while since I flew a Duchess, but many Pipers from that era had the pressure switch in addition to a squat switch. The Arrow in our club has both.

Go take a look at the left main landing gear, the squat switch is pretty obvious.

Joe

 

[Fearless Tower]

It does indeed have the switch, but (as I just found out talking to a Duchess owner), it appears that while they 'look' like squat switches, they don't actually work like squat switches - apparently they are only connected to the gear position indicator system.