Ball and screw u/c mech
 

hello all.
I'm considering installing a ball and screw mechanism as an undercarriage retraction system on a home-built.
Now, the problem with this low-friction mechanism is it requires a positive mechanical lock to hold the gear up. (current system is a screw jack which can't be reverse-driven).
I believe that there is a certified aircraft in the Piper/Cessna range that uses a solenoid brake to achieve this and would like to know more about both it's construction/design and indeed exactly what aircraft has this system fitted.
Can anyone help?
Thanks in advance

Many electrically powered rotary actuator are fitted with a solenoid brake - one that comes to mind is the B747 cargo door actuator system.The problem with your electrically powered jackscrew system is that you would have no free fall available in event of an actuator or electrical failure.

Further to your query - if my memory serves me right the 1960's Cessna 310 had electrically powered gear but I cannot recall how it operated.

Thanks for the reply but it I want to replace the current jack screw system, which doesn't free-fall, with a ball screw/worm gear which would free-fall, hence the need for the solenoid brake.

If you had an electrical problem how do you intend to release the solenoid brake? Is the brake intended to be the down lock also?

The sprung loaded solenoid would be the up lock and electrical failure would result in the gear having to be hand cranked down either by overcoming the brake friction or employing an emergency release mechanism.
(Maybe)!

The down lock is the existing over-centre mechanism.

Good luck with your project - keep us informed,too many of these queries are never heard from again.