Bo,

I am an instrumentation engineer and I am interested to design and built ANY part of my planes so also retracted gears. In the past I did make retracts already in pattern planes to experience the problems and results see the black and white pictures, Mäxi, with shorter nose and electrical activated retracts.

So in my situation it isn’t the question, why do you make retracts in an Orion, but, why do you use an Orion to invent retracts. This is the answer.

In the past it started as a Taurus, but after conversations, many years ago in a Taurus thread on RCU with Jim Messer, I did change my project to the Orion, two legs.
The fat wing of the Orion (or Taurus) has a lot of space to built in and try out an own designed system and the Orion did make already hundreds of flights until that spar he met and lost a wing.
Now I am finishing the design of the second generation gear set of my Orion.

My goal is design, build and use own designed systems and retracts are a real challenge!! (force distribution, fail safe, weight, complexity, maintenance, used components)
For example, because leakage is often a point of intention I do use only 3 o-rings in the whole system with plenty of spares!!!

So profits are, learning (most important!!) and nice to see (last picture) but not speed or flight characteristics.

Remarkable is, the Orion is/was 10 pounds , 4,5 kg and does fly excellent with a ENYE 60 4 stroke, so reduced drag maybe is a profit. The weight of the plane I always have to keep in mind when flying the plane (climbing!). Now, after finishing the plane next week I hope I did save some weight, but I still do not know how much. The reliability of the system again is most important.

About designing, I am preparing a new post about pneumatic retracts systems: “Wheel collar or constant differential pressure relay?”
So stay tuned about the retracts! Maybe in the future to show the “commercial suggested” method and an industrial solution for my Orion to control the speed of retract.

Cees