BVM Mig 15
- Kit
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$2,200.00
| 9/28/2008
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I received my Skymaster Gripen a month and ahalf ago. I had ordered the gray camo version and was very happy indeed upon opening the box and seeing the finish. It was beautiful.Well spent money i thought until i started building it. Dissapointment nr 1. The paint imediatly started to chip of if you were'nt very carefull handling the plane.Bad prep work pror to painting. The gel coat had'nt been properly scuffed and primed prior to painting. I always look for a builders manual before i start construction and read it from beginning to end.There was none included in the kit. I received a link to a manual of sorts from skymaster which i found extremly lacking in detail and information.It did not even mention were the hardwood blocks in the elevons were located. It was only thru dumb luck that i mounted the rod horns correctly. Imagine what could happen if a novice were to build this airplane? I built my airplane according to the sketchy info supplied from skymaster and were things were unclear i consulted a friend who has built 2 skymaster kits and is now starting on his third.
The day came for the maiden flight. I loaded up my truck with my prescious gripen and my trusty old Rookie + all the gear nesesary for a god days flying and then went to pick up another friend of mine who happens to be Norways most experienced and accomplished model airplane pilot. He had promised to help me with the first flight. We arrived at the field and i started asembly of my gripen.Then followed all obligatory checks. CG.Control throws. All sett up according the manual supplied by skymaster.Then onto tanks and fueling,checking for leaks,integrity of tanks,fuel drainage etc. Next was engine start, radio range test, taxi tests. Everything was found to be in perfect working order. back to depo, refueling and battery checks. Engine start of we trundel along the taxi way out to the runway. Full power was applied. Dissapointment number 2. Upon rotating the plane and climbing out it became appearant that it was severely tail heavy and nearly stalled. We got the nose down and accumulated speed and got up to safe altitude.The airplane was nowhere near what you could call stable in flight. pitchy as all hell!!! We flew a couple of rounds whilst debating a safe way to put the airplane back on the ground. while entering into a large right hand turn at 75 % throttle with a low bank angle the airplane deepstalls and enters into a flat spin subsequently tumbling slowly into the ground.
Again i repeat: the airplane was sett up as described in the manual for normal flight, suplied by skymaster.
Conclusion: CG as described in the manual must be completly wrong. control throws must be reduced by at least 50 percent both ways on the canard and the elevons reduced by at least 30% on elevator an aileron fuctions. I recommend that CG be moved forwards by at least 5 centimeters for normal flight"mode" and an additonal 3 centimeters for "beginner mode".
Damage: The underside looks like **** with paint having peeled of all over the place. the fuselage has several rips and tears in it where the wingspars enter the fuse. Engine hatch is cracked and has several holes in it after the engine mounting blocks came lose in the impact with the turbine smacking through it in several places. The aft end of the fuse has several places with burnt paint caused by a hot turbine roling freely around inside it.In other words my airplane looks like a 20 year old russian fighter which has nor had any TLC for said period.
Salvageable? Yes,but i dont know if i'm going to bother having lost faith in the product. We'll see..........
Posts: 1139
Joined: 12/8/2001 From: Virginia Beach,
VA, USA Status: offline
Erik, sorry to hear your ordeal. While I found the online manual not so helpful, I did set CG and throws accordingly and the Gripen flew absolutely perfect. The CG was in between the recommended beginners and advanced measurement with it being slightly behind the front (beginners) mark. We are still in the first few flights and getting the throws ironed out. The aileron roll is fast at the recommended throw if that's what you like. The elevator is very close and the canards are effective. The recommend you land with 50% canard throw. Again, I'm still working out the throws and these are my preliminary findings until i get more time on it.
Not a rep, just one of the first to assemble and fly the production kit.
Posts: 3017
Joined: 12/25/2001 From: old bridge, NJ, USA Status: offline
Not trying to minimize on the problems you had rookie, but i had a very positive experience with building my SM gripen. The paint on mine is also the all grey, and is very nice and durable .. i had built this plane on a very small desk in my home office (too many projects going on in the garage, it a mess in there ! ) and banged it around quite a bit ... I found the plane built very very strong, and only out of my own paranoia I ended up reinforcing a few joints with some aeropoxy... I was hoping to maiden the plane this weekend, but the weather sucks here, and im not happy with the pipe I had made myself ( so i just ordered one from Airpac and am waiting for it) Only problem point i found was the gear doors that had to be trimmed shaped (under heat) to fit nicely ... however this is typical with doors moulded separately from the plane .. i would have preferred just cutting the doors out of the fuselage ... but no big deal .. I only used the online instruction for CG and controll throw references, as everything else went in intuitively .. i do see however you point for a beginer building this plane having some problems ...
again, sorry for the trouble you had with your plane, but i did find this to be an incredible deal in terms of quality and price ..... look for a review of this plane here on RCU in the near future ..
Posts: 621
Joined: 5/24/2002 From: Honolulu,
HI, USA Status: offline
Hello Erik
I'm sorry to hear about your Gripen crashing, it is pretty amazing that even after spinning into the ground, the Gripen is still salvageable. One thing that I have found over the past year or so is that Skymaster Jets are though and durable.
I'm one of the test pilots for Airpac models and Skymaster in Hawaii, we have been flying the Gripen since November 2003.
Let me say first that I'm sure that you checked the CG before you flew, but my observations here are based on what you wrote in your post, it is not in anyway meant to question your ability to setup or build the airplane.
It sounds like the CG was too far aft, for whatever reason.
I have built or helped build / setup 3 Gripens and they have all been setup to have the cg at 140mm behind the leading edge of the wing.
Our test airplane had the cg as far back as 155mm from the leading edge of the wing. It would spin at that cg but you could recover, it would also do a really neat cobra type maneuver. (I have video let me know if you want to see it to compare with your accident ) It was more sensitive at this cg but flyable with some exponential.
Just today my friend flew the prototype Gripen 145 mm cg 5 times, I flew my gripen 3 times 147mm cg, even at 7mm back from the rear recommended cg it was very stable.
I measure my CG using a simple board with 2 holes drilled in to it. 2 dowels that are sanded to a very dull point are placed in the holes. We then tape a square of 1/16 in ply with mm markings on the ply to the bottom of the wing ( this is so the dowels will not damage the wings ) I will post a picture of it later.
In conclusion please double check your cg with no fuel ( UAT or hopper full ok ) and the gear down.
Please have faith in your Gripen it is a very fun airplane to fly, I'm sorry that you had such a bad experience with your first flight. I hope that you will have luck with it in the future. If you have any questions please feel free to contact me, I will gladly help you with whatever I can.
Here are some shot's from today. I hope they will inspire you to try it again.
The white one is powered by a Simjet 1700sp and the Red one is powered by a PST J600R.
< Message edited by Aero65 -- 8/15/2004 8:34:19 PM >
Hi Duke, Thanks for your reply. I have again measured the CG on my gripen and again its at 14 centimeters aft of leading edge,gear down.What control throws are you using on your gripens? Like you mentioned the roll rate was quick on mine.I also have the PST j 600 r in mine and my friend who was flying it said that there was ample power.I will take some pictures of mine and post them later. have to go to work now
Posts: 3267
Joined: 11/9/2002 From: Bakersfield, CA, USA Status: offline
That is terrible! I was getting ready to post another congrats post but I see that would have been bad in this case. Don't give up, if it is salvageable fix it. Good luck!
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Kenny Falconer - California Jets - April 3-6, 2008 www.ca-jets.com
That was really too bad....... Everyones nightmare.. I`ve been looking forward to see two Gripens at Rena next weekend..
I have also been in this situation before, but this was with a prop plane from Flair, a Cap 232. But do you think there was a logical explanation from the dealer or producer? Nope. Anyhow this prop-event was similar to yours. Glad you warned me, as mine will be airborne at Rena (hopefully). My understanding is that you won`t go for a second try with 140 mm, so what are you gonna do next time? If it can be rebuildt.. You have got some advices to fly at 140 mm even now.
So come on Gripen owners, what is your recommended CG setting!
Hallo Gudmund. Takk for sist! And thanks for your sympaties. I think i will consult with some of the other guys here who have experience with setting up and flying canard jets. Lets see what they say about this. I would like to have some feedback from skymaster about this. We'll see. I might be able to get it back together again for the Rena meet,but i'm not to keen on trying a second "maiden" up there.Besides i'm in the middle of selling my apartment(to many airplanes,not enough room) Kind of pushed for time.
Hi Duke Thank you again. I will make the airplane operational again and i will be needing as much detail as possible in order to avoid another "exciting flight.
Posts: 270
Joined: 1/14/2002 From: CUTLER BAY,
FL, USA Status: offline
Eric, Sorry about your Gripen. I flew my Gripen with the CG in between the 140 & 110 mm mark and needed 5 clicks of up elevons for level flight. I think it is a little nose heavy with so much up trim. I didn't experience any bad habits with this setup. Just that I need to come in slower for landing. I have it set for elevons & conards for takeoff and conards off when gear up. It flew very smooth like this. I have a P-120 dialed doun on it. I need to do more flight to see if I need to move the CG slightly back. Don't give up on the Gripen, it's a great jet for the $. Xcaliber
Posts: 4576
Joined: 12/6/2001 From: New Smyrna Beach,
FL, USA Status: offline
Erik, Very sorry to hear the misfortune you experienced with the maiden on the Gripen. There are however several now flying with the control throws and CG at the reccomended settings with flawless performance. I dont discount your ability to set the aircraft up properly but I do believe there must have been something faulty since the aircraft has proven to be very smooth and stable at the settings suggested. I do hope you can salvage your aircraft and try again. If there is anything I or skymaster can assist you with please dont hesitate to contact one of us (although, getting me right now may prove difficult for the next few days due to the severe storm that has passed thorough our state). Todd
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Maiden flight skymaster Gripen in Norway - 
Kind of pushed for time. 
