Rick Mullins

Started building: 2009 - First flight: December 2012

Rick Mullins

Rick Mullins First Flight 1 It took almost 4 years but I took the first flight yesterday. Everything went well and I was surprised to even have a little lift to work on a cold winter day.

First impressions: The sink rate and thermalling is awesome! Overall I can tell I'm going to have a good time with this. The day after Christmas I'm heading to Florida, warm weather, and thermals to get wired into this thing... [20 Dec 2012]

Videos

First Flight - 19th December 2012

This video clip is of a speed run to 70mph. I don't see any dimples in the leading edge but I could hear a couple of 'boinks'. I used 2 layers of the 5.7 oz. 284 twill fabric on my leading edges. I believe Steve did the same, but he added a light layer of fiberglass on top I think as a sacrificial layer to sand away to make it smooth. I made molds for my leading edges. Steve build his over plugs which gives you a rough surface.

 

Rick coming in to land at WestMar - video by Rose Pence.
Rick has added spoilers to his wings. You can see them as he passes the camera on finals. These replace the single delta-shaped spoiler behind the pilot's head which was of limited use.

"Mick at Wallaby Ranch said he mounted his spoilers on the spar line and worked fine. So I mounted mine in the same place and did a lot of work to make them flush and made an over center actuator to make them easy to operate. When I used them though the nose pitched down so much I could't level the glider. They are definitely mounted too far forward. Now I have a lot of work to do to remount them." - See the 'Notes' tab for an update and fix to this problem.

 

A view of the spoiler actuator mechanism inside Rick's wing.

 

Rick zooms along in ground effect!

 

Chasing Mick Robson's Carbon Dragon at Wallaby Ranch.

Calculations

Click >HERE< to download Rick's wing loading analysis spreadsheet.


Notes

Initial impressions after first flight:

[Rick] The controls will take a little getting used to. The roll control feels a little strange. I have no experience in sailplanes and only about 400 in small planes. The roll pressures are heavier than I expected and while the stick is mostly neutral in the center as you start getting to the extremes the stick wants to "fall" the rest of the way to the limit. Maybe a quirk of the way the way the triangular control block works as it goes over center or maybe I don't have something adjusted quite right? Maybe someone here who has flown one can comment...

[Russ] Dosen't sound right to me rick - my take on the diferent travel in aeleron...ie more on the up side than the down is to reduce adverse yaw. That why we dont have an even amount of travel. From what you are saying i suspect your bell crank is traveling futher than it should be allowed to.....and when it goes over centre the force is reversed and is snaping the stick to the side.
 
Dose this happen...from centre to ful left or right eleron....load netral centre stick......centering force increases as stick is pushed left or right.......near to far left or right force deminishes and close to end of the stick travel force diminishes and then starts to reverses and snaps to full travel?
 
If yes assemble the aircraft......fix one bungy cord up and one down on one flaperon to crate a nutraling force when it is deflected. Does the stick snap to full left and right?

[Rick] Russ asked..."dose this happen...from centre to ful left or right eleron....load netral centre stick......centering force increases as stick is pushed left or right.......near to far left or right force deminishes and close to end of the stick travel force diminishes and then starts to reverses and snaps to full travel?"

[Rick] That pretty much describes it. When I built it I tried to allow as much travel as possible but I may have over done it. When you move the stick the flapperons move in opposite directions, but most of the movement is in the up direction. The opposite flapperon is moving down but much less. Probably, as you say, to reduce adverse yaw. I did notice that at the extreme end of the travel, the flapperon going down will reverse direction and go back up slightly. I suspect that is when the stick gets weird. The weather has turned particularly nasty here of late so I won't have a chance to go out flying again before I head south with it next week. I'm going to Wallaby Ranch and there are 3 of them there so I'll have plenty of opportunity to figure out what is going on.

[Rick] Most of the flight I was flying an indicated 33-35 MPH. Without flaps I was getting stalls around 25. The documentation says it should stall at 22 so 25 without flaps sounds like it's in the ballpark. I flew it to 70 MPH and there I could hear my carbon leading edges start to 'boink" as they oil-canned. I suspect the spoiler would turbulate the airflow to the rudder, but this glider has a very large rudder... doesn't seem to be an issue. I never personally did any firing tests with this pneumatic rocket but there are videos here - www.secondchantz.com. Merry Christmas and Happy New Year.

[Rick] Re: wing-mounted spoilers: Mick at Wallaby Ranch said he mounted his spoilers on the spar line and worked fine. So I mounted mine in the same place and did a lot of work to make them flush and made an over center actuator to make them easy to operate. When I used them though the nose pitched down so much I could't level the glider. They are definitely mounted too far forward. Now I have a lot of work to do to remount them. [Update: Jun 2015 - Rick discovered why he was not able to correct the pitch-down problem even with the stick fully back. It turnd out that he did not give his elevator enough +/- travel when constructing it. The original plans call for the elevator to be able to move +/-30°. This is an easy problem to retro-fix, and Rick now has plenty of elevator control to counter the pitch-down he experiences with the air brakes fully deployed.]