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Supercub Thrust Line

My internet is running painfully slow today. Tried to get through this thread, but every page is taking a short lifetime to load.

Im considering the TLM, but have a few questions.

First concern is: Most airplanes have a negative engine angle to prevent pitch up stall conditions (think 737 Max) most noticed during full flap , full power go around conditions. Surprised that the developer doesn’t mention this, but maybe not an issue.

Second concern: On Wip amphibs a forward CG is an issue. I would love to have more room behind the engine, but How Much Will It Move My CG Forward?

Thanks
 
The theoretical pitching tendency has been addressed and the Super Cub does not try to pitch, thrustline mod or not. Doesn't change the CG that I am aware of or noticed.
 
Steve, you are the culprit behind my latest $$$ upgrade (TLM).

I watched your Hump Day presentation on inspections while I was 1000 miles from my cub. My cub was 18a-135 now 150. When you got to the part about engine mounts, I got curious about mine (installed with a reissue of Airworthiness and later inspected and stc’d with sa388ea). Armed only with under the hood pictures taken for other reasons, I couldn’t make out the engine mount gussets and thought for sure I would be changing my mount..... :(. Also, I didn’t know those cowel bumpers were missing. :).

Turns out I have the right mount.

Thanks for doing the inspection videos! Really looking forward to the future parts ii and iii (in a thankful, but $$$$scary kind of way)!
 
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Hi guys any suggestions I may have to go with a Dynafocal engine mount due to supply issues. Does anyone know of thrustline mods for Dyna mounts
 
I have got the CC 180hp STC (I know it has the swing out engine mount) on my PA-18-150, would I benefit from the thrustline mod or is it already part of that STC and new engine mount?
 
It is not part of the engine mount and if your wing incidence is correct and you are swinging a 1A200 McCauley prop it will make a difference.
 
I think the thrustline mod takes a little more to get used to than other mods. Your motor and cowl are obviously elevated and this changes the whole site picture ,especially if you are you have 2000 hrs in the normal config. Add 3 inch gear with 31's and forget looking over the cowl while taxiing. The mod in my opinion is for someone looking to max performance takeoffs from off airport locations , otherwise....
 
I never notice a change in my site picture. I drop the nose bowl down as far as I can above the ring hear and don't really believe I lost any visibility over the nose. It was ready to fly before I thought it was and I would over shoot my landing spot at first till I got use to it.
 
My experience after a YOUNG A&P installed the T&Lmod at New Holstein was a bit shorter take off,a couple knots faster airspeed and thecubjust felt lighter, more responsive under power.


Sent from my iPhone using SuperCub.Org
 
Was the Thrustline Mod ever STC'd for the -12?? It sounds like it might resolve some of my trim challenges.
Check that the leading edge of the stabilizer sits on the top longeron when trimmed full nose up. Found a local -12 which was not and was nose heavy, Fixed it and trim troubles were gone.
 
Thanks much.

I'm fairly certain that it does but I'll give a look later today. I think I'm also going to weigh it next week as well. It is new to me and I want to make sure the former owner & I got good info from the builders.
 
Thanks much.

I'm fairly certain that it does but I'll give a look later today. I think I'm also going to weigh it next week as well. It is new to me and I want to make sure the former owner & I got good info from the builders.
The cross tube which carries the tube connecting the stabilizers which bolts to the trim casting needs to be below the bolts not above. You will need to remove the stabilizers to relocate it. If that is your issue. I'll be curious to learn if that is your issue.
 
Just did the first flight of my Super Cub clone. It flew great except having to carry a good deal of nose down trim. When I reduced power had to start trimming nose up. Say three cranks either way. Stabilizer in neutral trim is level with water line, engine is 90 degrees to the water line, and wing incidence is at 1.4 degrees. Aircraft empty center of gravity is 14 inches aft of leading edge. Every thing in flight is fine. Flys very well hands off, just have to set trim about half of nose down trim. Any ideas of where to look.
Thanks
 
Just did the first flight of my Super Cub clone. It flew great except having to carry a good deal of nose down trim. When I reduced power had to start trimming nose up. Say three cranks either way. Stabilizer in neutral trim is level with water line, engine is 90 degrees to the water line, and wing incidence is at 1.4 degrees. Aircraft empty center of gravity is 14 inches aft of leading edge. Every thing in flight is fine. Flys very well hands off, just have to set trim about half of nose down trim. Any ideas of where to look.
Thanks

How are you determining the " waterline"? With the aircraft level (firewall perpendicular to ground) Stabilizer should have 2.5 degrees up travel and 4 degrees down travel. First thing I would do is load it to max gross weight with CG to the back limit and see if you run out of nose down trim (stabilizer up)? Every plane is a little different, you are making great speed for a cub. As long as you can trim with a full and empty load sounds like you are doing well.
DENNY
 
Thanks for the comments. I have the required travel for the stabilizer, Water line was a laser beam from the tip of the tail post and running with the upper tube of fuselage window ledge left side with the laser set at level. The fuselage was built from the northland plans, so the ledge turned out to be the most level place on the fuselage. It has all the mods, including performance flaps, but only 700x6 tires, so one reason for speed I expect. Will go with larger tires when these get wore some.
 
There are times an asymmetric surface on the Vfin or horizontal has value, As you increase airflow it increases it's counteraction to the forces. Most every plane I have designed and built in the past needed reshaping the horizontal providing nearly no manual trim changes through the flight realm.

The flat tail surfaces on these planes offer no natural changes of lift forces with changes of thrust or airspeed which means you have to adjust it yourself.
 
Anyone got more contact info for Mark (thrustline) can’t get him in the phone number on his site and I don’t see another option, cell/email etc.

edit- message machine off or full

Thank you
 
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