TBM Shock Jet
08-20-2019, 07:44 AM
#1461
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Location: Lathrop, MO
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Hey Tom...
Does your SJ NOT have flaps??? That thing does NOT need to land that fast! Also do you not have throttle control either?? Looks as if you are full throttle ALL the time.
Just wondering......
Does your SJ NOT have flaps??? That thing does NOT need to land that fast! Also do you not have throttle control either?? Looks as if you are full throttle ALL the time.
Just wondering......
08-20-2019, 09:23 AM
#1462
Hi,
Thanks for the info,
Being only jet in my country (sad I know...) I dont have someone beside me to look into it.
I have some CG issue obviously but manual does not cover it completely.
SJ is around 12.5-13kg AUW.
My turbine could not fit as back as I would like, a forme beam stands above it, and starter motor in front prevents tank to go further back...
So my whole tank is in front of CG, not on it.
If I balance the plane spot on with batteries, dry tank, with filled UAT, when i fill 2.7-3liters of fuel it is nose heavy.
I land with around 1liter left in main tank and full UAT.
Do you suggest to balance it with that landing fuel level,
nose heavy/full on takeoff is tolerable, but landing with New setting could be slower?
As now the elevator can not hold nose up to bleed it off before touchdown.
Thanks for any info
Thanks for the info,
Being only jet in my country (sad I know...) I dont have someone beside me to look into it.
I have some CG issue obviously but manual does not cover it completely.
SJ is around 12.5-13kg AUW.
My turbine could not fit as back as I would like, a forme beam stands above it, and starter motor in front prevents tank to go further back...
So my whole tank is in front of CG, not on it.
If I balance the plane spot on with batteries, dry tank, with filled UAT, when i fill 2.7-3liters of fuel it is nose heavy.
I land with around 1liter left in main tank and full UAT.
Do you suggest to balance it with that landing fuel level,
nose heavy/full on takeoff is tolerable, but landing with New setting could be slower?
As now the elevator can not hold nose up to bleed it off before touchdown.
Thanks for any info
08-21-2019, 12:10 AM
#1463
I took some photos to visualize setup. Do you think tank and turbine should go further back? I would have to cut one beam that is limiting the turbine. Hope that mod is not needed...
Will try to set CG with wing on and compare to Manual(fuselage point) since gear position does not seem same from photos and could be misleading when setting CG from its position rather than wing itself.
Will try to set CG with wing on and compare to Manual(fuselage point) since gear position does not seem same from photos and could be misleading when setting CG from its position rather than wing itself.
Last edited by dr.tom; 08-21-2019 at 03:15 AM.
08-21-2019, 05:21 AM
#1464
My Feedback: (13)
My K-70 mounted behind that rear former that your turbine is butted up against. Plenty of room for it there, That entire bay where you have your turbine and tank I used for a large fuel tank, which ends up exactly on CG that way. Half the turbine is visible from the exterior in this position. It also made it easier to achieve the indicated CG. Your CG looks about correct. The CG instructions available when I put mine together called for 1-3/4# ( from memory) nose weight on the nose gear- I had no dimension to work from.
Flaps make a big difference. Mine will stop in 100 feet of touchdown easily. I also discovered that too much flaps will almost stop the plane in mid air, I was using 70 deg full, 35 deg at half. I had to cut that down to maintain a smooth landing.
Good luck with yours, they are fun.
John
Flaps make a big difference. Mine will stop in 100 feet of touchdown easily. I also discovered that too much flaps will almost stop the plane in mid air, I was using 70 deg full, 35 deg at half. I had to cut that down to maintain a smooth landing.
Good luck with yours, they are fun.
John
08-21-2019, 11:38 AM
#1465
Thanks for the help,
that landing was with full flaps as pictured below,
but cg is too much forward,
now I have printed lighter front wheel which is around 120grams lighter, and cg should be much better with landing fuel level.
the suggested CG based on distance from main gear (1 1/2 inch) with wings on is not ok on this one,
it calls for 3 inches (double) based on measurements of wing, body, gear placement...
if it does not help, I will have to take turbine out and rethink clamp mechanism to fit it a bit lower and further back.
that landing was with full flaps as pictured below,
but cg is too much forward,
now I have printed lighter front wheel which is around 120grams lighter, and cg should be much better with landing fuel level.
the suggested CG based on distance from main gear (1 1/2 inch) with wings on is not ok on this one,
it calls for 3 inches (double) based on measurements of wing, body, gear placement...
if it does not help, I will have to take turbine out and rethink clamp mechanism to fit it a bit lower and further back.
Last edited by dr.tom; 08-21-2019 at 11:46 AM.
08-22-2019, 01:01 PM
#1468
Thnx for all suggestions, things are getting better now with new CG 
just have to watch out for intruders on the runway (2:00)
just have to watch out for intruders on the runway (2:00)
Last edited by dr.tom; 08-22-2019 at 01:05 PM.
08-22-2019, 05:19 PM
#1469
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Check my video out....
No flaps on take off.... But slow landing...
No flaps on take off.... But slow landing...
Thnx for all suggestions, things are getting better now with new CG
just have to watch out for intruders on the runway (2:00)
https://www.youtube.com/watch?v=zh6iNZV7TD4
just have to watch out for intruders on the runway (2:00)
https://www.youtube.com/watch?v=zh6iNZV7TD4
08-27-2019, 12:57 AM
#1472
Nice,
I was thinking about Shocky, do you still have it?
Can you measure CG on your wing, not fuselage like in Manual, please.
I posted wing dimensions 2-3 posts up, so would like to compare them with yours if no problem(wingspan, root and chord dimensions)
Currently i have CG fluctuation of 4 cm from empty/full main tank and still tuning the best one for slower landing yet not too tailheavy when tank is used up at end of the flight...
Thanks a lot.
https://www.youtube.com/watch?v=j3iXewfOU9s
Pic from weekend flying:
I was thinking about Shocky, do you still have it?
Can you measure CG on your wing, not fuselage like in Manual, please.
I posted wing dimensions 2-3 posts up, so would like to compare them with yours if no problem(wingspan, root and chord dimensions)
Currently i have CG fluctuation of 4 cm from empty/full main tank and still tuning the best one for slower landing yet not too tailheavy when tank is used up at end of the flight...
Thanks a lot.
https://www.youtube.com/watch?v=j3iXewfOU9s
Pic from weekend flying:
Last edited by dr.tom; 08-27-2019 at 01:10 AM.
