Kingtech presents the all new T1 sports jet
06-27-2018, 04:55 AM
#1727
Got mine maidened finally!!!
had to bellyland it, since one of the wheels got stuck in the wheelwell... seems the're a bit tight.... anyone else had this issue??
otherwise the plane flies perfectly!! sure to have lots of fun with it!
mine's powered with a Graupner G-Booster 160+ turned down to 129K rpm, which should be about 15kg of thrust for a 11.34kg plane (empty tanks, full UAT)
I just have to find some paint.
07-08-2018, 10:42 AM
#1734
Just a quick heads up to all T1 owners, I had a major flutter issue on the tail of mine, after flying for a couple of minutes my spotter told me to shut the throttle and slow down as he could see the right stabliser/elevator fluttering, I got the plane back to the runway and landed although a bit heavy as the elevator response was not so good.
On the ground you could see the right stab was hanging at an angle, on inspection the bolts that hold the clamp fitting to the former were loose I checked the bolts for the other stab & fin and they were not tight either.
I should have checked them when I put the plane together and used threadlock, but as these came pre installed I let it pass.
The two formers the clamps are attached to will need repairing as they have both cracked and there is damage to the skin between the fin and stab .
This shouldn't be too difficult to repair and I'll definitely be beefing up the former between the two clamps.
So the message is check all the bolts on all the clamps ( including wings) are tight.
Really like the T1 and the way it flies just glad it didn't become a total loss as so often happens when surfaces suddenly start to flutter.
On the ground you could see the right stab was hanging at an angle, on inspection the bolts that hold the clamp fitting to the former were loose I checked the bolts for the other stab & fin and they were not tight either.
I should have checked them when I put the plane together and used threadlock, but as these came pre installed I let it pass.
The two formers the clamps are attached to will need repairing as they have both cracked and there is damage to the skin between the fin and stab .
This shouldn't be too difficult to repair and I'll definitely be beefing up the former between the two clamps.
So the message is check all the bolts on all the clamps ( including wings) are tight.
Really like the T1 and the way it flies just glad it didn't become a total loss as so often happens when surfaces suddenly start to flutter.
07-08-2018, 04:41 PM
#1735
Just a quick heads up to all T1 owners, I had a major flutter issue on the tail of mine, after flying for a couple of minutes my spotter told me to shut the throttle and slow down as he could see the right stabliser/elevator fluttering, I got the plane back to the runway and landed although a bit heavy as the elevator response was not so good.
On the ground you could see the right stab was hanging at an angle, on inspection the bolts that hold the clamp fitting to the former were loose I checked the bolts for the other stab & fin and they were not tight either.
I should have checked them when I put the plane together and used threadlock, but as these came pre installed I let it pass.
The two formers the clamps are attached to will need repairing as they have both cracked and there is damage to the skin between the fin and stab .
This shouldn't be too difficult to repair and I'll definitely be beefing up the former between the two clamps.
So the message is check all the bolts on all the clamps ( including wings) are tight.
Really like the T1 and the way it flies just glad it didn't become a total loss as so often happens when surfaces suddenly start to flutter.
On the ground you could see the right stab was hanging at an angle, on inspection the bolts that hold the clamp fitting to the former were loose I checked the bolts for the other stab & fin and they were not tight either.
I should have checked them when I put the plane together and used threadlock, but as these came pre installed I let it pass.
The two formers the clamps are attached to will need repairing as they have both cracked and there is damage to the skin between the fin and stab .
This shouldn't be too difficult to repair and I'll definitely be beefing up the former between the two clamps.
So the message is check all the bolts on all the clamps ( including wings) are tight.
Really like the T1 and the way it flies just glad it didn't become a total loss as so often happens when surfaces suddenly start to flutter.
07-08-2018, 07:43 PM
#1737
Hello all,
I'm gonna add to this thread. I would like piggy back on rfbenn's post about loose pinch clamps.
I always noticed that the horizontal stabs were a little "loose" when I tightened the pinch clamps down on both the FWD and AFT dowels that come from the horizontal stab to the fuselage. I just thought that I wasn't tightening the bolts that close the pinch clamps enough, but boy howdy was I applying torque enough that I thought any second now I'll strip out the bolts. so I flew it for a few flights, checked the bolts that tighten the pinch clamps, and sure enough they were tight!!!!! OK, there must be something else I've over looked, as the HORZ stabs should NOT be that "wobbly!" OK, time to investigate. I took both left and right HORZ stabs off, and looked inside the AFT fuselage where the pinch clamps are installed, and wouldn't you know it, many of the bolts that hold the clamps to the bulkheads are either loose or missing!!!! Well, I took every bolt out that mounts the clamps to the bulkheads in ALL locations to include the pinch clamps for both wings, and applied loctite on every bolt at EVERY location on the bird. It looked like some of those bolts were being held in place by what appeared to be a bit of glue that was used to glue the bulkheads in place and the extra glue was just "dropped" over the head of the bolts that hold the pinch clamps in place. Since I've tightened all those bolts that hold the pinch clamps in place to the bulkheads, ALL flight control surfaces are super tight, no wobble at all, the HORZ stabs are rock solid. I found like 3 bolts just sitting in the bottom of the fuse below the thrust tube, so PLEASE, PLEASE inspect those bolts that hold the clamps in place, I'm sure you'll find some loose or missing.
I'm gonna add to this thread. I would like piggy back on rfbenn's post about loose pinch clamps.
I always noticed that the horizontal stabs were a little "loose" when I tightened the pinch clamps down on both the FWD and AFT dowels that come from the horizontal stab to the fuselage. I just thought that I wasn't tightening the bolts that close the pinch clamps enough, but boy howdy was I applying torque enough that I thought any second now I'll strip out the bolts. so I flew it for a few flights, checked the bolts that tighten the pinch clamps, and sure enough they were tight!!!!! OK, there must be something else I've over looked, as the HORZ stabs should NOT be that "wobbly!" OK, time to investigate. I took both left and right HORZ stabs off, and looked inside the AFT fuselage where the pinch clamps are installed, and wouldn't you know it, many of the bolts that hold the clamps to the bulkheads are either loose or missing!!!! Well, I took every bolt out that mounts the clamps to the bulkheads in ALL locations to include the pinch clamps for both wings, and applied loctite on every bolt at EVERY location on the bird. It looked like some of those bolts were being held in place by what appeared to be a bit of glue that was used to glue the bulkheads in place and the extra glue was just "dropped" over the head of the bolts that hold the pinch clamps in place. Since I've tightened all those bolts that hold the pinch clamps in place to the bulkheads, ALL flight control surfaces are super tight, no wobble at all, the HORZ stabs are rock solid. I found like 3 bolts just sitting in the bottom of the fuse below the thrust tube, so PLEASE, PLEASE inspect those bolts that hold the clamps in place, I'm sure you'll find some loose or missing.
07-08-2018, 11:10 PM
#1739
07-24-2018, 06:39 AM
#1740
T-1 model Fortune repair/modification
I thought I'd add some pictures to show my fix for the pinch clamp bolts coming loose that nearly caused the loss of my T-1 , see post 1734 above.
In the first picture you can see that I have taken out the bolts and replaced them with studs , I used 4mm socket head bolts screwed in tight with stud lock and then cut off the heads. The thinking behind this was that you can always tighten a nut up but bolts that go into blind holes can only tighten up so far before you have either shorten the bolt or pack out with washers as the plywood former compresses.
I have done the same with the pinch clamp on the fin too as this loosened due to the tail flutter.
The 3mm aluminium/ aluminum plate is shaped to go across the former and tie the two pinch clamps together making the whole arrangement a lot more rigid.
The carbon faced ply piece is glued to the next former forward that takes the front pinch bolts to brace the splits in the former.
http://www.rcuniverse.com/forum/atta...1&d=1532440544
This picture shows the plate in place with the pinch clamp studs going through the original former first and secured with nylock nuts, further back you can see the carbon plate in place too
http://www.rcuniverse.com/forum/atta...1&d=1532440544
Last picture shows where the stucture is nearly ready for painting I have backed up the the damaged areas with heavy weight glass fibre cloth and epoxy resin and the airframe is nice and rigid again
http://www.rcuniverse.com/forum/atta...1&d=1532440544
I have had a good look at the wing clamps and they are fine and still tight, these are attached with through bolts and don't appear to suffer in the same way as the ones in the blind holes, I have had a couple of friends look at the tail retaining system and we think that the bolts have bottomed out and the plywood former has compressed enough to let them loosen.
Hopefully with my modification that should never happen again.
Looking forward to getting the T-1 in the air again shortly.
Rob
In the first picture you can see that I have taken out the bolts and replaced them with studs , I used 4mm socket head bolts screwed in tight with stud lock and then cut off the heads. The thinking behind this was that you can always tighten a nut up but bolts that go into blind holes can only tighten up so far before you have either shorten the bolt or pack out with washers as the plywood former compresses.
I have done the same with the pinch clamp on the fin too as this loosened due to the tail flutter.
The 3mm aluminium/ aluminum plate is shaped to go across the former and tie the two pinch clamps together making the whole arrangement a lot more rigid.
The carbon faced ply piece is glued to the next former forward that takes the front pinch bolts to brace the splits in the former.
http://www.rcuniverse.com/forum/atta...1&d=1532440544
This picture shows the plate in place with the pinch clamp studs going through the original former first and secured with nylock nuts, further back you can see the carbon plate in place too
http://www.rcuniverse.com/forum/atta...1&d=1532440544
Last picture shows where the stucture is nearly ready for painting I have backed up the the damaged areas with heavy weight glass fibre cloth and epoxy resin and the airframe is nice and rigid again
http://www.rcuniverse.com/forum/atta...1&d=1532440544
I have had a good look at the wing clamps and they are fine and still tight, these are attached with through bolts and don't appear to suffer in the same way as the ones in the blind holes, I have had a couple of friends look at the tail retaining system and we think that the bolts have bottomed out and the plywood former has compressed enough to let them loosen.
Hopefully with my modification that should never happen again.
Looking forward to getting the T-1 in the air again shortly.
Rob
07-24-2018, 07:46 AM
#1741
To Rick75 & 737Driver
Guys, just a question, are either of you using a gyro on your T-1's, I was asked the same question and I am using a Demon coretex pro on mine,the thinking being that maybe the gain on mine was a bit high and that gyro action may have started the bolts loosening, although when I first set mine up there was no oscillation visible on any surfaces when flat out.
Rob
Guys, just a question, are either of you using a gyro on your T-1's, I was asked the same question and I am using a Demon coretex pro on mine,the thinking being that maybe the gain on mine was a bit high and that gyro action may have started the bolts loosening, although when I first set mine up there was no oscillation visible on any surfaces when flat out.
Rob
07-24-2018, 02:57 PM
#1743
To Rick75 & 737Driver
Guys, just a question, are either of you using a gyro on your T-1's, I was asked the same question and I am using a Demon coretex pro on mine,the thinking being that maybe the gain on mine was a bit high and that gyro action may have started the bolts loosening, although when I first set mine up there was no oscillation visible on any surfaces when flat out.
Rob
Guys, just a question, are either of you using a gyro on your T-1's, I was asked the same question and I am using a Demon coretex pro on mine,the thinking being that maybe the gain on mine was a bit high and that gyro action may have started the bolts loosening, although when I first set mine up there was no oscillation visible on any surfaces when flat out.
Rob
Hey Rob!
I have a Powerbox Cockpit system installed. I got a deal on it, and bonus, it sequences doors, the only door I have on the T1 is the nose gear door. The Powerbox Cockpit is a bit overkill for the T1, but it works super!!! That is the long way to say that, YES, I do have a gyro installed on the T1. It's the iGyro SRS from Powerbox as well. I fly mostly with gyro turned OFF as the plane doesn't need it, I had it and thought what the heck throw it in there. Sure on gusty windy days, it comes in handy, and it sure does reduce your work load on approach, but you should be able to handle an approach with no gyro anyhow. I installed it cause I got it in a deal package with the Powerbox Cockpit. The iGyro SRS is hooked up to a GPS antenna to sense speed that cuts the gain down as the plane accelerates rather than having to mess with a potentiometer on your radio when flying. I would venture a guess to say NO, the oscillations you may have experienced with a high gain setting on your gyro would have really no effect on loosening bolts. That would be some severe oscillations and I would think that your flight control surfaces would depart the aircraft way before a bolt loosened, especially if said bolts would have loctite applied to them.
I really like your fix for your horz and vert stab area, very robust! I may implement that someday down the road when I send my engine for TBO, until the mean time, I put a ton of loctite on my bolts that hold the pinch clamps to the bulkhead, I'm pretty sure they ain't going anywhere!!!!!
07-25-2018, 11:34 PM
#1745
Thanks 737 I agree that I can't see the gyro being the problem either but will reset it just in case. Like you say the T-1 really doesn't need a gyro and the first dozen flights I flew without but put the Coretex in to see if it made much of a difference, gyro's a nice thing to have on a windy day but not needed on this airframe.
07-26-2018, 11:54 AM
#1746
Does anyone make an off the rack sun shade for the T-1? I'm set to fly mine in a demo for an RC Airshow in a couple weeks and don't really want it laying around in direct sun light for several hours.