Close

F-35 predecessor

A project log for Apartment ventilation system

The 25 year battle to get fresh air in tiny apartments

lion mclionheadlion mclionhead 12/20/2021 at 18:450 Comments

Interesting predecessor to the F-35 nozzle built by the soviet union.  

http://www.leteckemotory.cz/motory/r-79/index.php?en

Of note for lions is the use of a torque tube & a complicated mechanism for nozzle opening.  It has 4 swiveling sections & the exit doesn't rotate.  It has a jig which keeps the exit from rotating, thus providing a rigid platform for the last actuator to push against.  It has 3 motors with 1 freewheeling bearing.  The lion version has 3 swiveling sections & the exit rotates.

It was used in the yak-141

https://en.wikipedia.org/wiki/Yakovlev_Yak-141

It had 3 engines.  2 vertically mounted, afterburning engines replaced the lift fan in the nose & only ran when hovering.  Lockheed paid a certain amount for the nozzle design.  It must have been envisioned as a hovering weapons platform.

1.5 years on, air vent model #F-35 has shown its age.  The front motor no longer has enough brake torque to keep it in a sideways right angle.  Once it slips, the encoders have to be reset.  The brushes must have worn down or the friction in the bearing must have worn down.  Farsteners have started falling off.  It is now known that PLA is threadlock safe.  

There would be some major redesigns.  Quadrature motor encoding would be the biggest change.  A new nozzle would be built before discarding the old one.  It would have to be manually reset in order to access more range.  

Discussions