Scorpion update
04-15-2007, 01:08 PM
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Scorpion update
Scorpion update:
Weight = 25lbs dry
Power = Jetcat P80
Radio JR9303
Fuel 2.2 liter main tank, 24oz additional and UAT
Flights = 49
Mishaps = 5
There was some talk about the quality of this kit and the sloppy stabilizer mount set-up, I agree that the stab mount could a tighter fit but it has proven to be a good design and on 4 occasions it has been not only satisfactory but almost bullet proof! I have dead stick landed into brush that tore through a wing (ran out of fuel), landed off to the side of the runway into the desert, plowed into the desert short of the runway, split open a stabilizer, split open both wing tips, ripped the main gear out, locked the brakes up so hard that the tires look like cubes and finally bounced so hard that I ripped the wood in the nose apart. The plane is tough!! And yes it lives to fly again. I know this sound like my flying sucks but I’m really not that bad. I have come to term that since my normal flying is done on a dry lakebed and precise landings are not required, I need to get to a standard runway for practice and I may need to check my eyeglass prescription
[8D]. All things considered this is one tough plane and takes abuse very well.
Weight = 25lbs dry
Power = Jetcat P80
Radio JR9303
Fuel 2.2 liter main tank, 24oz additional and UAT
Flights = 49
Mishaps = 5
There was some talk about the quality of this kit and the sloppy stabilizer mount set-up, I agree that the stab mount could a tighter fit but it has proven to be a good design and on 4 occasions it has been not only satisfactory but almost bullet proof! I have dead stick landed into brush that tore through a wing (ran out of fuel), landed off to the side of the runway into the desert, plowed into the desert short of the runway, split open a stabilizer, split open both wing tips, ripped the main gear out, locked the brakes up so hard that the tires look like cubes and finally bounced so hard that I ripped the wood in the nose apart. The plane is tough!! And yes it lives to fly again. I know this sound like my flying sucks but I’m really not that bad. I have come to term that since my normal flying is done on a dry lakebed and precise landings are not required, I need to get to a standard runway for practice and I may need to check my eyeglass prescription
[8D]. All things considered this is one tough plane and takes abuse very well. 
But I fixed that ticking problem with a little thin epoxy
04-15-2007, 04:41 PM
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RE: Scorpion update
Glad to hear that it's tuff.... William, thanks for answering all my PM's. I got rid of almost all the slop in the rear stabs. Pretty tight now. Goin to recheck my CG. Fired it up at the field yesterday and noticed that the nose is lite. I will take your suggestion and use the main wheels as the center for my CG. One little issue with on of my behotec main gear sticking. After that,,,,she's ready. Oh yea, our field is under water right now too. But after that.....
Thanks again William
Hoss
Thanks again William
Hoss
04-15-2007, 10:13 PM
#5
RE: Scorpion update
William,
All those things you write about sound like normal flying operations from what I've seen and from I've experienced. I think you fly that scorpion great, even with a hotspot hitting your flying station while you were flying!! Great flyin' [sm=thumbup.gif]
Raf
All those things you write about sound like normal flying operations from what I've seen and from I've experienced. I think you fly that scorpion great, even with a hotspot hitting your flying station while you were flying!! Great flyin' [sm=thumbup.gif]
Raf
04-16-2007, 05:39 PM
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RE: Scorpion update
William
Hoping to maiden my Scorp this Saturday. How much flap travel are you using and how much up elevator mix with flap. As per instructions or any different? Don't want to find out how tough it is just yet!
John
Hoping to maiden my Scorp this Saturday. How much flap travel are you using and how much up elevator mix with flap. As per instructions or any different? Don't want to find out how tough it is just yet!
John
04-16-2007, 05:55 PM
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RE: Scorpion update
I have my flaps set up per the instructions and it takes a little more than the recomended elevator mix to keep the nose up. Not bad once you know it and she never feels out of control.
04-16-2007, 06:04 PM
#8
RE: Scorpion update
ORIGINAL: john agnew
William
Hoping to maiden my Scorp this Saturday. How much flap travel are you using and how much up elevator mix with flap. As per instructions or any different? Don't want to find out how tough it is just yet!
John
William
Hoping to maiden my Scorp this Saturday. How much flap travel are you using and how much up elevator mix with flap. As per instructions or any different? Don't want to find out how tough it is just yet!
John
Dave
04-16-2007, 08:47 PM
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RE: Scorpion update
Hey guys, For what it's worth. My Scorpion weighed in at 21 pounds dry and NO nose weight to balance it. The 2 batteries made it a tad nose heavy. I set the CG even with the main wheels as William did. So, All I need a dry field and it's ready to go. I will keep you guys updated. Thanks for all the information gentelman
Hoss
Hoss
04-16-2007, 09:16 PM
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RE: Scorpion update
Lil Hoss you set your c/g on the struts correct? Not the tires but the strut, even though mine still feels slightly nose heavy in flight.
04-16-2007, 09:35 PM
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RE: Scorpion update
Yes William, the Strut. I just went and measured it and it's 61/4" from the root of where the wing attaches. And as I said before, A little nose heavy. I can always adjust after the maiden flight.
Hoss
Hoss
04-23-2007, 04:16 AM
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RE: Scorpion update
Guys
At last I got to maiden the Scorpion on Saturday. It started off a lousy day for a test flight with drizzle and low cloud, very poor visibility, most of the guys chose not to fly and departed around lunchtime. A few of us hung around and eventually the weather improved and I decided to go for it.
The Scorpion tracked very straight with very little steering input and lifted off very smoothly ( no take off flap) she banked and climbed out very nicely and I entered a trimming circuit, three click of left aileron and two of up elevator and she was flying hands off, I needed about 3/4 power on the Wren Supersport to maintain a cruising speed and with full power the model was not particularily fast. It is a big , draggy model for a 54 sized turbine and I really feel it needs something like an Artes Falcon or equal for best performance. Due to the low cloud ceiling I did not try any vertical moves on the first flight, rolls were a bit slow indicating that more aileron movement and maybe less expo are required.
Flap input showed no pitch tendencies and I selected full flap (45o) on the downwind leg, eased back to idle on final approach and managed a greaser right in front of the pilot position. Flap / elevator mix was 12mm up at the trailing edge of the elevator with full flap. I did not fly again as the weather was closing in.
Conclusions. The Scorpion flies very well, is easy to see with the big vertical stabs and is a *****cat to land, I think it needs at least 22lbs of thrust and I may derate my Merlin and try that sometime soon.
John
At last I got to maiden the Scorpion on Saturday. It started off a lousy day for a test flight with drizzle and low cloud, very poor visibility, most of the guys chose not to fly and departed around lunchtime. A few of us hung around and eventually the weather improved and I decided to go for it.
The Scorpion tracked very straight with very little steering input and lifted off very smoothly ( no take off flap) she banked and climbed out very nicely and I entered a trimming circuit, three click of left aileron and two of up elevator and she was flying hands off, I needed about 3/4 power on the Wren Supersport to maintain a cruising speed and with full power the model was not particularily fast. It is a big , draggy model for a 54 sized turbine and I really feel it needs something like an Artes Falcon or equal for best performance. Due to the low cloud ceiling I did not try any vertical moves on the first flight, rolls were a bit slow indicating that more aileron movement and maybe less expo are required.
Flap input showed no pitch tendencies and I selected full flap (45o) on the downwind leg, eased back to idle on final approach and managed a greaser right in front of the pilot position. Flap / elevator mix was 12mm up at the trailing edge of the elevator with full flap. I did not fly again as the weather was closing in.
Conclusions. The Scorpion flies very well, is easy to see with the big vertical stabs and is a *****cat to land, I think it needs at least 22lbs of thrust and I may derate my Merlin and try that sometime soon.
John
04-23-2007, 04:54 AM
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RE: Scorpion update
Congrats on your Maiden John. Sounds like it flies well. Looks like next weekend for my Scorpion. Our field is drying out nicely. As I said before, I have a P80 pushing 19- 20 pounds of thrust on a 21 pound jet. Should be fine. As the weather breaks by you and you get more flights in, keep us informed on your flights.
Thanks
Hoss
Thanks
Hoss
04-23-2007, 09:54 AM
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RE: Scorpion update
I just finished up the successful test flights on my scorpion. Like every one above has said the plane fly’s very nice and stable. Mine is also balanced on the main strut and is still somewhat nose heavy in the air. I have approx 6 flights and removed weight from the nose after every flight! I only have 9oz left and will probably remove that, after some more flights. I had to put another up elevator mix in, when the speed brake is used as it wants to pitch down slightly. Now with all mixing set, using takeoff, landing flaps and speed brake and spoilers (ailerons mixed up) have no pitch effects on the plane.
Mine is powered by a Behotec JB66 (19lbs) motor and like the above statements, requires ¾ to full throttle for fun flight. Something in the mid 20lbs thrust would better suit this plane. Even still it is a keeper as it is one of the better looking sport planes. Looks like a cross between a F5 and F18 to me.
Mine is powered by a Behotec JB66 (19lbs) motor and like the above statements, requires ¾ to full throttle for fun flight. Something in the mid 20lbs thrust would better suit this plane. Even still it is a keeper as it is one of the better looking sport planes. Looks like a cross between a F5 and F18 to me.
04-23-2007, 12:46 PM
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RE: Scorpion update
I have the max throws available, limited only by linkage. I know that I have more throw on the elevator than the book recommends (I have forgot was it is, but I can go back and re measure).
I started with 45% expo on the elevators which was too soft for me, so I am down to around 25% expo now on the elevators. Zero on the ailerons, and 20% on the rudder. It has good rudder authority, but belly pitches a lot in knife edge flight.
I have the AD Angel and its roll rate with full throws and no expo is very sluggish, the scorpion seems to roll ½ again faster than my angel.
I don’t use dual rates, so my models are a little more sensitive than other people’s set-ups. Part of being a helicopter flyer, it will always make your fixed wing flying better and smoother!
As far as the mixes go, it was just trial and error. I believe I started with a ¼ inch up for the first notch of flaps (½ travel) and then around a 1/8th up for the full flap setting. I think I used around ¼ up for the speed brake. Spoilers are mixed up 70% of their full travel.
The spoilers really help on landing as it keeps the plane settling consistently, even when in ground effect.
In other words you can pick a spot on the runway and aim for it and land very close to it every time. You won’t float and float, and float and float and then go plop on the ground way past where you intended to land.
I started with 45% expo on the elevators which was too soft for me, so I am down to around 25% expo now on the elevators. Zero on the ailerons, and 20% on the rudder. It has good rudder authority, but belly pitches a lot in knife edge flight.
I have the AD Angel and its roll rate with full throws and no expo is very sluggish, the scorpion seems to roll ½ again faster than my angel.
I don’t use dual rates, so my models are a little more sensitive than other people’s set-ups. Part of being a helicopter flyer, it will always make your fixed wing flying better and smoother!
As far as the mixes go, it was just trial and error. I believe I started with a ¼ inch up for the first notch of flaps (½ travel) and then around a 1/8th up for the full flap setting. I think I used around ¼ up for the speed brake. Spoilers are mixed up 70% of their full travel.
The spoilers really help on landing as it keeps the plane settling consistently, even when in ground effect.
In other words you can pick a spot on the runway and aim for it and land very close to it every time. You won’t float and float, and float and float and then go plop on the ground way past where you intended to land.
04-23-2007, 12:47 PM
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RE: Scorpion update
I have the max throws available, limited only by linkage. I know that I have more throw on the elevator than the book recommends (I have forgot was it is, but I can go back and re measure).
I started with 45% expo on the elevators which was too soft for me, so I am down to around 25% expo now on the elevators. Zero on the ailerons, and 20% on the rudder. It has good rudder authority, but belly pitches a lot in knife edge flight.
I have the AD Angel and its roll rate with full throws and no expo is very sluggish, the scorpion seems to roll ½ again faster than my angel.
I don’t use dual rates, so my models are a little more sensitive than other people’s set-ups. Part of being a helicopter flyer, it will always make your fixed wing flying better and smoother!
As far as the mixes go, it was just trial and error. I believe I started with a ¼ inch up for the first notch of flaps (½ travel) and then around a 1/8th up for the full flap setting. I think I used around ¼ up for the speed brake. Spoilers are mixed up 70% of their full travel.
The spoilers really help on landing as it keeps the plane settling consistently, even when in ground effect.
In other words you can pick a spot on the runway and aim for it and land very close to it every time. You won’t float and float, and float and float and then go plop on the ground way past where you intended to land.
I started with 45% expo on the elevators which was too soft for me, so I am down to around 25% expo now on the elevators. Zero on the ailerons, and 20% on the rudder. It has good rudder authority, but belly pitches a lot in knife edge flight.
I have the AD Angel and its roll rate with full throws and no expo is very sluggish, the scorpion seems to roll ½ again faster than my angel.
I don’t use dual rates, so my models are a little more sensitive than other people’s set-ups. Part of being a helicopter flyer, it will always make your fixed wing flying better and smoother!
As far as the mixes go, it was just trial and error. I believe I started with a ¼ inch up for the first notch of flaps (½ travel) and then around a 1/8th up for the full flap setting. I think I used around ¼ up for the speed brake. Spoilers are mixed up 70% of their full travel.
The spoilers really help on landing as it keeps the plane settling consistently, even when in ground effect.
In other words you can pick a spot on the runway and aim for it and land very close to it every time. You won’t float and float, and float and float and then go plop on the ground way past where you intended to land.
04-23-2007, 02:33 PM
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RE: Scorpion update
ORIGINAL: john agnew
Guys
At last I got to maiden the Scorpion on Saturday. It started off a lousy day for a test flight with drizzle and low cloud, very poor visibility, most of the guys chose not to fly and departed around lunchtime. A few of us hung around and eventually the weather improved and I decided to go for it.
The Scorpion tracked very straight with very little steering input and lifted off very smoothly ( no take off flap) she banked and climbed out very nicely and I entered a trimming circuit, three click of left aileron and two of up elevator and she was flying hands off, I needed about 3/4 power on the Wren Supersport to maintain a cruising speed and with full power the model was not particularily fast. It is a big , draggy model for a 54 sized turbine and I really feel it needs something like an Artes Falcon or equal for best performance. Due to the low cloud ceiling I did not try any vertical moves on the first flight, rolls were a bit slow indicating that more aileron movement and maybe less expo are required.
Flap input showed no pitch tendencies and I selected full flap (45o) on the downwind leg, eased back to idle on final approach and managed a greaser right in front of the pilot position. Flap / elevator mix was 12mm up at the trailing edge of the elevator with full flap. I did not fly again as the weather was closing in.
Conclusions. The Scorpion flies very well, is easy to see with the big vertical stabs and is a *****cat to land, I think it needs at least 22lbs of thrust and I may derate my Merlin and try that sometime soon.
John
Guys
At last I got to maiden the Scorpion on Saturday. It started off a lousy day for a test flight with drizzle and low cloud, very poor visibility, most of the guys chose not to fly and departed around lunchtime. A few of us hung around and eventually the weather improved and I decided to go for it.
The Scorpion tracked very straight with very little steering input and lifted off very smoothly ( no take off flap) she banked and climbed out very nicely and I entered a trimming circuit, three click of left aileron and two of up elevator and she was flying hands off, I needed about 3/4 power on the Wren Supersport to maintain a cruising speed and with full power the model was not particularily fast. It is a big , draggy model for a 54 sized turbine and I really feel it needs something like an Artes Falcon or equal for best performance. Due to the low cloud ceiling I did not try any vertical moves on the first flight, rolls were a bit slow indicating that more aileron movement and maybe less expo are required.
Flap input showed no pitch tendencies and I selected full flap (45o) on the downwind leg, eased back to idle on final approach and managed a greaser right in front of the pilot position. Flap / elevator mix was 12mm up at the trailing edge of the elevator with full flap. I did not fly again as the weather was closing in.
Conclusions. The Scorpion flies very well, is easy to see with the big vertical stabs and is a *****cat to land, I think it needs at least 22lbs of thrust and I may derate my Merlin and try that sometime soon.
John
having a great time in the north west tip of scotland
can not find any safe place to fly my glider too many rocks
see you friday (which plane are you droping off )
04-23-2007, 02:54 PM
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RE: Scorpion update
Andy
I am going to need a bigger fuel tank for the Merlin! Will try again with the Supersport before making the switch. Will probably bring the Foxcub on Sat. weeather forecast is looking good at the moment.
John
I am going to need a bigger fuel tank for the Merlin! Will try again with the Supersport before making the switch. Will probably bring the Foxcub on Sat. weeather forecast is looking good at the moment.
John
04-23-2007, 02:59 PM
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RE: Scorpion update
Don
I started out with 25% expo on elevator and that seems about right, also I gave it 10mm more elevator travel than the book suggests. I have 25% expo on aileron which I will remove and try for a bit more throw as well. Funnily enough I was never aware of the Phoenix being slow in roll and it has the same wing as the Scorpion. This is the first Jet I have flown without dual rates, I don't think low rates would be very usefull on this model as it need all the throw you can get!
John
I started out with 25% expo on elevator and that seems about right, also I gave it 10mm more elevator travel than the book suggests. I have 25% expo on aileron which I will remove and try for a bit more throw as well. Funnily enough I was never aware of the Phoenix being slow in roll and it has the same wing as the Scorpion. This is the first Jet I have flown without dual rates, I don't think low rates would be very usefull on this model as it need all the throw you can get!
John
