Mailing List lml@lancaironline.net Message #53396
From: <Sky2high@aol.com>
Sender: <marv@lancaironline.net>
Subject: Re: [LML] Re: 290 Gear-Up electrical short?
Date: Fri, 06 Nov 2009 00:35:11 -0500
To: <lml@lancair.net>
Sven,
 
Egads!  So much for over automating functions.  Interesting, because the pump motor doesn't like to run in both directions at the same time.  However, since there is a pressure band in which the pressure switch will remain open - in this case, just long enough for the up side to start and break an over-center link - the result you mention is well within reason.  But, it is impossible to imagine that full retraction of all the gear could take place.
 
Dang, what a dangerous mess to have only one gear collapse on landing when the full belly in is so satisfying.
 
Yes, "don't be too smart!"
 
Grayhawk
 
In a message dated 11/5/2009 8:20:46 P.M. Central Standard Time, sven.jerlhagen@gmail.com writes:
I have seen this happen in a friends 360. There was a modified wiring:
 
1. From the gear selector up side there was a throttle position switch to start a buzzer (gear warning)
2. A float switch also energized the same buzzer for low fuel warning
 
Now if you are a little low on gas when you enter final the fuel will slosh forward from the deceleration and close the float switch. The power will go back thru the low throttle switch and energize the gear up relay even though the gear selector is in down position. The gear down relay is off since the pressure switch is open on the down side
 
In my friends case it only partly retracted one gear, which collapsed on rollout. Goes to show any wiring modificaion must be carefully analyzed, and dont be too smart :)
 
Sven Jerlhagen
SE-XOP
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster