Technic MOC jet aircraft landing gear pneumatics

[Andy G]

Hey Folks,

Ive been working on making a large scale technic jet and as part of that process have been developing landing gear systems using pneumatics. I have tried to replicate the real thing by creating mechanically sequenced systems that use no electronics. These systems replicate that of older generation jets such as Boeing 727's and the like. The first tricky part has been developing a four way pneumatic valve using the three psition lego pneumatic switches. The second has been making an overcentre locking brace to secure the gear in the extended position. Only problem is I havent been able to make the pneumatic nose wheel steering proportional. Anyway let me know what you think :)

Andy

[efferman]

very good work

how big the jet will be when it is finished?

[DLuders]

@ Andy G: Welcome to Eurobricks! I think your model is close to the real Boeing 727's Main Landing Gear retraction (

by eclipso104):

Edited July 7, 2012 by DLuders

[allanp]

Looks awesome so far

[Andy G]

very good work

how big the jet will be when it is finished?

Ah Im looking at making it like a dc-8 super 60 (its scaled by one so far with regards to fuselage cross section and gear height) so probably a couple of meters long. Ive got heaps to do yet though, might be another year to get it done but Ill stick at it.

@ Andy G: Welcome to Eurobricks! I think your model is close to the real Boeing 727's Main Landing Gear retraction

Thanks!

[dhc6twinotter]

That looks really great! The sequencing is well done.

Are you building an Airbus A330 or A340? The landing gear looks a bit like the A330 or A340 main landing gear.

Nice work, and I'm looking forward to the finished project!

[Saberwing40k]

Welcome! This model, aside from the colors, is amazing. I'll be waiting to see progress. So, do you have any pictures, and if so, where?

Anywho, if you want proportional control, you might want to implement something like this:

Be warned, however, that it is huge, and frighteningly complex. It is indeed proportional.

Link for more pictures and info.

[Andy G]

That looks really great! The sequencing is well done.

Are you building an Airbus A330 or A340? The landing gear looks a bit like the A330 or A340 main landing gear.

Nice work, and I'm looking forward to the finished project!

Thanks! Im looking at making a dc-8 but there are so many systems I want to try and replicate from different aircraft I might just make it a generic jet. For instance Ive made a flap system that uses geometric principles similar to a 767 so the model could go in any direction.

Welcome! This model, aside from the colors, is amazing. I'll be waiting to see progress. So, do you have any pictures, and if so, where?

Anywho, if you want proportional control, you might want to implement something like this:

Be warned, however, that it is huge, and frighteningly complex. It is indeed proportional.

Thanks for that. I havent got any pictures up yet as Ive been developing the model in modules so I have bits everywhere atm. I actually replicated this proportional control a while ago and got it running. That Mark Bellis is a real genius. The problem is the size of it makes it quite prohibitive in its application. Id love to adapt it for flight control actuation. Has anyone tried to shrink this model down?

[Blakbird]

Incredible work! I've worked Landing Gear Actuation on several airplane programs and your models are remarkably accurate. I've always preferred the older airplanes with mechanical sequencing.

As for the proportional nose wheel steering, real airplanes use commutator valves and control manifolds to accomplish that, so good luck!