BVM Composite Bandit Build Thread. Yes from 1998.
#1
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BVM Composite Bandit Build Thread. Yes from 1998.
Look what I found! I plan to use it as my aileron trainer. I thought it would be fun to document this "before my time" jet.
Back in 1998 I came home on leave from Aviano, Italy. Little did I know someone was buying me a nice BVM Bandit in Lincoln, Nebraska. It would find me 18 years later.
Let see what we have here first and later I'll layout the plan.
Wings, tanks, turbine kit, gear, its all there.
Sexy
Clear Canopy
Box full of Goodies, hardware, valves, air line, everything.
Ram 750 install kit, like the truck??
They used to come with a ****load of cocaine. "Raw Materials", Good one!
I suppose they figured you are already smoking crack for paying that much in the first place.
Original external air cylinders
Original gear and a set of purple retracts I plan to use.
Original BVM smooth stop, V1
PPG$ Primer
They used to put cow urine in the epoxy back then apparently.
Heres a question to start it off, I have the original single wall pipe which has to be built up to a dual wall. Its seems kinda flimsy, is it up to the task of a K140g? (27-30 lbs of thrust).
Also what was the weight of the original ram 750 turbine? I'd like to see how much the K140g will weigh it down.
Back in 1998 I came home on leave from Aviano, Italy. Little did I know someone was buying me a nice BVM Bandit in Lincoln, Nebraska. It would find me 18 years later.
Let see what we have here first and later I'll layout the plan.
Wings, tanks, turbine kit, gear, its all there.
Sexy
Clear Canopy
Box full of Goodies, hardware, valves, air line, everything.
Ram 750 install kit, like the truck??
They used to come with a ****load of cocaine. "Raw Materials", Good one!
I suppose they figured you are already smoking crack for paying that much in the first place.
Original external air cylinders
Original gear and a set of purple retracts I plan to use.
Original BVM smooth stop, V1
PPG$ Primer
They used to put cow urine in the epoxy back then apparently.
Heres a question to start it off, I have the original single wall pipe which has to be built up to a dual wall. Its seems kinda flimsy, is it up to the task of a K140g? (27-30 lbs of thrust).
Also what was the weight of the original ram 750 turbine? I'd like to see how much the K140g will weigh it down.
Last edited by essyou35; 03-08-2016 at 10:10 PM.
#2
Probably worth talking with BVM. I'd change the pipe, the early ones were always on the limit and when they collapse its a mess! The Bandit also came out nose heavy with later lighter turbines.
Think the RAM 750 was based on a KJ 66 so like a JetCat P-80-120.That would have been a bare turbine on gas start, so turbine unit weight verses installed weight is different to now with valves and pumps installed internally. The ram was probably an ounce or two lighter on the turbine, but I remember their pumps, wiring etc being heavy.
Think the RAM 750 was based on a KJ 66 so like a JetCat P-80-120.That would have been a bare turbine on gas start, so turbine unit weight verses installed weight is different to now with valves and pumps installed internally. The ram was probably an ounce or two lighter on the turbine, but I remember their pumps, wiring etc being heavy.
Last edited by Dave Wilshere; 03-09-2016 at 12:26 AM.
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After reading this, I dug out my old RAM 750 air start manual. The installed weight of just the engine was 2.2 lbs. The manual has no other weights listed for the peripherals.
My first one was S/N 42.
I would recommend getting a double wall pipe. BVM could make one, or you could get on from Tam.
You can purchase a Smooth Stop II upgrade piston from BVM. It's worth the money.
When you look inside, some of the "cow urine" you are seeing is really Kevlar clioth. It's yellow in color.
The resin yellowing is caused by UV light exposure, and time. Some resins contain a UV stabilizing agent, but it's effect is minimal.
My first one was S/N 42.
I would recommend getting a double wall pipe. BVM could make one, or you could get on from Tam.
You can purchase a Smooth Stop II upgrade piston from BVM. It's worth the money.
When you look inside, some of the "cow urine" you are seeing is really Kevlar clioth. It's yellow in color.
The resin yellowing is caused by UV light exposure, and time. Some resins contain a UV stabilizing agent, but it's effect is minimal.
#4
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When you installed weight, do you mean that accounts for everything like the pump etc? At 2.2 lbs that is lighter than a modern K100g at 2.9 lbs for just the motor. The K140g I will be using will be at 3.7 lbs.
Should help get some weight back there for balance. When I assemble this I will ensure I put things back further.
Sounds like the fiberglass is ok from my previous thread. It had me worried but it seems strong.
Should help get some weight back there for balance. When I assemble this I will ensure I put things back further.
Sounds like the fiberglass is ok from my previous thread. It had me worried but it seems strong.
#5
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The pipe mounting scheme is overly complicated. Including the double wall nozzle .
Copy the SB pipe mounting system if you can. And check the pipe wall thickness. They increased it dramatically, fairly early on.
The single biggest thing you can do is change out the landing gear (including moving the inner door cylinders). How are you going to get the purple gear into the wings?
Oh reinforce the cowl to fuselage joints from the inside too
Copy the SB pipe mounting system if you can. And check the pipe wall thickness. They increased it dramatically, fairly early on.
The single biggest thing you can do is change out the landing gear (including moving the inner door cylinders). How are you going to get the purple gear into the wings?
Oh reinforce the cowl to fuselage joints from the inside too
Last edited by mr_matt; 03-09-2016 at 07:28 AM.
#6
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According to Harley from a previous conversation, they can be made to fit by reversing the cylinders. I have not honestly looked into it yet. However, given how thick the wings are I am not sure what the issue is anyways. There is a ton of room in there.
I agree, I will find a pipe somewhere or make my own.
I'll figure a way to mount the pipe, I had to do it on my SM mig as they don't even given you a way. I do notice it has a bypass I am not sure if the one I have will work with the turbine I am going to use. I am not I'll even use the bypass.
Are you talking about the main top hatch?
I agree, I will find a pipe somewhere or make my own.
I'll figure a way to mount the pipe, I had to do it on my SM mig as they don't even given you a way. I do notice it has a bypass I am not sure if the one I have will work with the turbine I am going to use. I am not I'll even use the bypass.
Are you talking about the main top hatch?
The pipe mounting scheme is overly complicated. Including the double wall nozzle .
Copy the SB pipe mounting system if you can. And check the pipe wall thickness. They increased it dramatically, fairly early on.
The single biggest thing you can do is change out the landing gear (including moving the inner door cylinders). How are you going to get the purple gear into the wings?
Oh reinforce the cowl to fuselage joints from the inside too
Copy the SB pipe mounting system if you can. And check the pipe wall thickness. They increased it dramatically, fairly early on.
The single biggest thing you can do is change out the landing gear (including moving the inner door cylinders). How are you going to get the purple gear into the wings?
Oh reinforce the cowl to fuselage joints from the inside too
#7
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I don't know how you could reverse the cylinders but Harley is clever.
The clearance issue would not be the wing thickness. The superbandit wing they are designed for is the same thickness. The issue is the hole mounting pattern, the gear mount depth in relation to the wing and mainly the clearance for the operating cylinders (but you said you are going to reverse those so that would not be an issue).
I was not referring to the main hatch but the cheek inlet cowls. You have to glue them on in a classic bandit. I just liked to reinforce the back side of that joint.
I would not run without a bypass but of course that is your business. BVM flow path engineering is the best. And your turbine is much safer in a crash. And that thing will be very fast and I am not sure I would trust all of that ram air to find its way out of the fuse without popping hatches off.
The clearance issue would not be the wing thickness. The superbandit wing they are designed for is the same thickness. The issue is the hole mounting pattern, the gear mount depth in relation to the wing and mainly the clearance for the operating cylinders (but you said you are going to reverse those so that would not be an issue).
I was not referring to the main hatch but the cheek inlet cowls. You have to glue them on in a classic bandit. I just liked to reinforce the back side of that joint.
I would not run without a bypass but of course that is your business. BVM flow path engineering is the best. And your turbine is much safer in a crash. And that thing will be very fast and I am not sure I would trust all of that ram air to find its way out of the fuse without popping hatches off.
Last edited by mr_matt; 03-09-2016 at 08:30 AM.
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1Eye (04-23-2022)
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Matt just brought up a couple of very good points.
Never fly the Bandit without using the bypass, and cover.
Years ago a friend (who will go nameless) flew his without the bypass cover after ignoring my warning not to do so. A short time after take off, well below top speed, the air pressure from the inlet blew the engine hatch off, allowing the canopy hatch to slide aft and blow off the airplane. Not only was the jet very tail heavy at that point, but the vertical fin and the canopy transparency were damaged when the canopy hatch struck the fin leading edge. It could have been worse.
Also, to parrot what Matt stated, forget the plastic header tank, and make a tank out of the Kevlar cover by gluing another BVM tank vent fitting to the top forward end, and installing another BVM tank feed fitting and receptacle centered on the forward end of the tank. Aeropoxy the tank halves together and you have a Kelvar header tank.
If you send your purple gear to BVM, Casey can reverse them very easily. No additional parts are required. They will end up looking like a set for the BVM AFS T-33. I would think an hours labor would cover it, but call Patty to make sure.
Never fly the Bandit without using the bypass, and cover.
Years ago a friend (who will go nameless) flew his without the bypass cover after ignoring my warning not to do so. A short time after take off, well below top speed, the air pressure from the inlet blew the engine hatch off, allowing the canopy hatch to slide aft and blow off the airplane. Not only was the jet very tail heavy at that point, but the vertical fin and the canopy transparency were damaged when the canopy hatch struck the fin leading edge. It could have been worse.
Also, to parrot what Matt stated, forget the plastic header tank, and make a tank out of the Kevlar cover by gluing another BVM tank vent fitting to the top forward end, and installing another BVM tank feed fitting and receptacle centered on the forward end of the tank. Aeropoxy the tank halves together and you have a Kelvar header tank.
If you send your purple gear to BVM, Casey can reverse them very easily. No additional parts are required. They will end up looking like a set for the BVM AFS T-33. I would think an hours labor would cover it, but call Patty to make sure.
#13
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Also if the kit is that early, make SURE to put the forward bolt on the fin. If you don't put that forward bolt in you stand a good chance of fluttering the whole fin with a 140 on board.
And I would swap out CF fin post for a steel one.
I agree it will go very fast. And the fin is the first thing to go.
And I would swap out CF fin post for a steel one.
I agree it will go very fast. And the fin is the first thing to go.
#14
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Great tips, I knew this thread would be helpful.
BTW, I am using the 140 not because I want to make it go super fast. That is not my intention ever.
I have a 140 in my JL viper and I never push it full bore except after a slow pass when I want a strong climbout.
I enjoy strong vert lines and the ability to pull out from near stall speed.
If I see this jet getting fast I will back off, I have nothing to prove.
The other reason is the 140 is more versatile with the different jets it goes in, and now I have two 140s so that opens the door for an a-10 in the next few years if I decide to go that route and the turbines last that long.
BTW, I am using the 140 not because I want to make it go super fast. That is not my intention ever.
I have a 140 in my JL viper and I never push it full bore except after a slow pass when I want a strong climbout.
I enjoy strong vert lines and the ability to pull out from near stall speed.
If I see this jet getting fast I will back off, I have nothing to prove.
The other reason is the 140 is more versatile with the different jets it goes in, and now I have two 140s so that opens the door for an a-10 in the next few years if I decide to go that route and the turbines last that long.
#15
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Even if you use that Kevlar hopper you will have about 94 ounces (I can't remember exactly). So keep that in mind.
That was another pretty big change for the super bandit. It holds about 25 ounces more fuel. 2 to 2.5 minutes roughly.
Depending on your motor choice you may or may not need the speedbrake.
That was another pretty big change for the super bandit. It holds about 25 ounces more fuel. 2 to 2.5 minutes roughly.
Depending on your motor choice you may or may not need the speedbrake.
#16
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I have about 100 oz in my viper and can fly 5 mins with time to spare.
Im used to short flights.
I didn't even know it has a speedbrake. I haven't read the textbook of a manual it comes with.
Tomorrow I'll post what servos and equipment I want to use. The first step will be to figure out if I can reverse the cylinders myself, will post about that a bit.
Im used to short flights.
I didn't even know it has a speedbrake. I haven't read the textbook of a manual it comes with.
Tomorrow I'll post what servos and equipment I want to use. The first step will be to figure out if I can reverse the cylinders myself, will post about that a bit.
Even if you use that Kevlar hopper you will have about 94 ounces (I can't remember exactly). So keep that in mind.
That was another pretty big change for the super bandit. It holds about 25 ounces more fuel. 2 to 2.5 minutes roughly.
Depending on your motor choice you may or may not need the speedbrake.
That was another pretty big change for the super bandit. It holds about 25 ounces more fuel. 2 to 2.5 minutes roughly.
Depending on your motor choice you may or may not need the speedbrake.
#17
I'll figure a way to mount the pipe, I had to do it on my SM mig as they don't even given you a way. I do notice it has a bypass I am not sure if the one I have will work with the turbine I am going to use. I am not I'll even use the bypass.
Are you talking about the main top hatch?
Mounting the pipe is easy using the typical BVM method..
.
Please Please take the advice of Harley and others here. The Bypass/internal ducting is the best you can get. Don't even think about running without it. Disaster will surely follow.
A K140 comp Bandit will be a Monster.. It is possible, but will be CRAZY fast, and HEAVY.. You will need to be on your toes all the time while flying.. And landings will need to be precise.. Here is my Balsa Bandit in action. https://www.youtube.com/watch?v=hzGaXweytNc . (Same air frame as yours.) powered by a PST 600 a mere 13 lb thrust turbine, and 19 lbs all up weight.. Watch how slow it lands..
My advise would be a K 100. This combo will easily exceed 200 mph level flight, and be much friendlier/forgiving in the pattern. Your choice of course..
Enjoy it.. This kit, although quite old, was designed and built in Florida, to BVMs high standards. Brilliant air planes..
Roger
#18
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BTW there is a BVMP bypass and pipe from a mig 15 in the classifieds, will that do me any good with this jet?
http://www.rcuniverse.com/market/ite...itemId=1064619
http://www.rcuniverse.com/market/ite...itemId=1064619
#19
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I will definitely be using that advice. Im not convinced its going to be much heavier than the Ram 750 install. I've seen an old ram 1000 which is just a 750 over clocked, and it looks huge like an iron lung!
If anything, I would think it will be about 1-2 lb heavier and from my experience with jets it wont make any different.
I worked HARD to reduce the weight of a jet I had from 32 lbs to 27 lbs and it made no noticeable difference.
Maybe Im wrong and this one matters.
My JL viper I used to run a K100 and it gained a few lbs when I put in the K140 and it made 0 difference on landing speeds. If anything, I usually find 100N airframes to be underpowered for some reason.
I do have a K100 but I put it in my YA f-18. An equally over powered jet.
BTW, before I start cutting this thing up, I would entertain offers, and am open to trades.
Normally I would never own a bandit but I got lucky.
I just finished up a Yellow aircraft f-18 so I think I have the skills but Im more of an arf guy.
If anything, I would think it will be about 1-2 lb heavier and from my experience with jets it wont make any different.
I worked HARD to reduce the weight of a jet I had from 32 lbs to 27 lbs and it made no noticeable difference.
Maybe Im wrong and this one matters.
My JL viper I used to run a K100 and it gained a few lbs when I put in the K140 and it made 0 difference on landing speeds. If anything, I usually find 100N airframes to be underpowered for some reason.
I do have a K100 but I put it in my YA f-18. An equally over powered jet.
BTW, before I start cutting this thing up, I would entertain offers, and am open to trades.
Normally I would never own a bandit but I got lucky.
I just finished up a Yellow aircraft f-18 so I think I have the skills but Im more of an arf guy.
Wow. Awesome indeed. You have a real bargain here!! (A tad better than $20 Raff) Being a Bandit fan, I am just a little bit jealous ...
Mounting the pipe is easy using the typical BVM method..
.
Please Please take the advice of Harley and others here. The Bypass/internal ducting is the best you can get. Don't even think about running without it. Disaster will surely follow.
A K140 comp Bandit will be a Monster.. It is possible, but will be CRAZY fast, and HEAVY.. You will need to be on your toes all the time while flying.. And landings will need to be precise.. Here is my Balsa Bandit in action. https://www.youtube.com/watch?v=hzGaXweytNc . (Same air frame as yours.) powered by a PST 600 a mere 13 lb thrust turbine, and 19 lbs all up weight.. Watch how slow it lands..
My advise would be a K 100. This combo will easily exceed 200 mph level flight, and be much friendlier/forgiving in the pattern. Your choice of course..
Enjoy it.. This kit, although quite old, was designed and built in Florida, to BVMs high standards. Brilliant air planes..
Roger
Mounting the pipe is easy using the typical BVM method..
.
Please Please take the advice of Harley and others here. The Bypass/internal ducting is the best you can get. Don't even think about running without it. Disaster will surely follow.
A K140 comp Bandit will be a Monster.. It is possible, but will be CRAZY fast, and HEAVY.. You will need to be on your toes all the time while flying.. And landings will need to be precise.. Here is my Balsa Bandit in action. https://www.youtube.com/watch?v=hzGaXweytNc . (Same air frame as yours.) powered by a PST 600 a mere 13 lb thrust turbine, and 19 lbs all up weight.. Watch how slow it lands..
My advise would be a K 100. This combo will easily exceed 200 mph level flight, and be much friendlier/forgiving in the pattern. Your choice of course..
Enjoy it.. This kit, although quite old, was designed and built in Florida, to BVMs high standards. Brilliant air planes..
Roger
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essyou35 - You will love it. Here is a pic of mine. I had no hand in the building or painting or re-painting Jeremy Ferguson in BC built and painted it (twice - original scheme was black and too hard to see.)
I have an EvoJet Booster 130 in it. It is very, very fast if I want it to be. I have the front hopper tank in there. I can fly 6 mins, land and taxi back and still have the hopper full. With the 130 very little throttle is needed to fly at a comfortable 150-170mph or so. You don't need much thrust at all to maintain those "slow" speeds. Crank it open and you can turn it in to a speeding nearly invisible dot scary fast.
Harvey - couple of questions if you don't mind...
The idea for the hopper in the hatch is a great one. I am squeezing in a plastic tank and while it works it's not ideal. Do you happen to have any pictures of the hopper you built in to the hatch?
My SB flies and lands like a dream. My only issue has been takeoff from grass - it gets very (dangerously in fact) squirrely. There are no signs of anything catching on the ground (tanks, gear doors etc.) I have the Dreamworks trailing-link gear on it and the springs seem too soft (even the "extra stiff" ones) but still not so soft that anything hits the ground. I'm hoping a nose gyro will help and also the technique for Bandits of holding up elevator seemed to work a couple of times (but not always.) I considered putting the regular struts back on but I'm concerned the pounding it will get on grass. Our grass is really smooth and nice but its a lot of load on the gear with the small wheels and relatively long takeoff roll. Any ideas? Perhaps it's just that I need to do like the manual says and just hold the elevator up for the whole takeoff run (feels very unnatural.)
I have an EvoJet Booster 130 in it. It is very, very fast if I want it to be. I have the front hopper tank in there. I can fly 6 mins, land and taxi back and still have the hopper full. With the 130 very little throttle is needed to fly at a comfortable 150-170mph or so. You don't need much thrust at all to maintain those "slow" speeds. Crank it open and you can turn it in to a speeding nearly invisible dot scary fast.
Harvey - couple of questions if you don't mind...
The idea for the hopper in the hatch is a great one. I am squeezing in a plastic tank and while it works it's not ideal. Do you happen to have any pictures of the hopper you built in to the hatch?
My SB flies and lands like a dream. My only issue has been takeoff from grass - it gets very (dangerously in fact) squirrely. There are no signs of anything catching on the ground (tanks, gear doors etc.) I have the Dreamworks trailing-link gear on it and the springs seem too soft (even the "extra stiff" ones) but still not so soft that anything hits the ground. I'm hoping a nose gyro will help and also the technique for Bandits of holding up elevator seemed to work a couple of times (but not always.) I considered putting the regular struts back on but I'm concerned the pounding it will get on grass. Our grass is really smooth and nice but its a lot of load on the gear with the small wheels and relatively long takeoff roll. Any ideas? Perhaps it's just that I need to do like the manual says and just hold the elevator up for the whole takeoff run (feels very unnatural.)
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Here are some photos of the original Kevlar hopper tank shield. It's .the round one in the photos.
On a virgin kit tank shield, add a round hole for a BVM Tank stopper in one end, and install a BVM vent fitting as appear on the Super Bandit hopper tank as shown in the photos.
Aeropoxy the two halves together, and you have a 24 ounce hopper tank to replace the 16 ounce Sullivan tank.
On the round one shown in the photos, you can see the large diameter hole in the end, which must be covered by a disk of G-10 , and then penetrated for the BVM tank stopper.
As an alternative, BVM sells the large Super Bandit Kevlar hopper tank for $155.00, part number is K5300-55. It fits between the inlets. You will then have 3.6 liters of fuel.
It is shown installed in my Super Bandit.
Looks like I duplicated one of the photos....rats!
Last edited by Harley Condra; 03-12-2016 at 02:20 AM.
#24
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A size comparison to my JL viper. As you can see the viper is bigger and more draggy. Huge canopy, taller and thicker airframe. Much bigger vert fin too.
However the K140 is the correct turbine for it and the K100 is weak sauce in it. It still lands like a putty cat. Even with the K140, though I never open it up much past 3/4 on straight lines, its not breaking 150mph by much. However the takeoffs are vertical.
Wings are similar in airfoil and size. The Bandits wings are wider and the vipers wings are longer (excluding winglet).
Not the best compare since I am neglecting the tails.
Don't know why the pics are updside down but whatever.
So going to think the K140 over and maybe consider a K100.
However the K140 is the correct turbine for it and the K100 is weak sauce in it. It still lands like a putty cat. Even with the K140, though I never open it up much past 3/4 on straight lines, its not breaking 150mph by much. However the takeoffs are vertical.
Wings are similar in airfoil and size. The Bandits wings are wider and the vipers wings are longer (excluding winglet).
Not the best compare since I am neglecting the tails.
Don't know why the pics are updside down but whatever.
So going to think the K140 over and maybe consider a K100.
Last edited by essyou35; 03-10-2016 at 07:11 PM.
#25
essyou35 -
My SB flies and lands like a dream. My only issue has been takeoff from grass - it gets very (dangerously in fact) squirrely. There are no signs of anything catching on the ground (tanks, gear doors etc.) I have the Dreamworks trailing-link gear on it and the springs seem too soft (even the "extra stiff" ones) but still not so soft that anything hits the ground. I'm hoping a nose gyro will help and also the technique for Bandits of holding up elevator seemed to work a couple of times (but not always.) I considered putting the regular struts back on but I'm concerned the pounding it will get on grass. Our grass is really smooth and nice but its a lot of load on the gear with the small wheels and relatively long takeoff roll. Any ideas? Perhaps it's just that I need to do like the manual says and just hold the elevator up for the whole takeoff run (feels very unnatural.)
My SB flies and lands like a dream. My only issue has been takeoff from grass - it gets very (dangerously in fact) squirrely. There are no signs of anything catching on the ground (tanks, gear doors etc.) I have the Dreamworks trailing-link gear on it and the springs seem too soft (even the "extra stiff" ones) but still not so soft that anything hits the ground. I'm hoping a nose gyro will help and also the technique for Bandits of holding up elevator seemed to work a couple of times (but not always.) I considered putting the regular struts back on but I'm concerned the pounding it will get on grass. Our grass is really smooth and nice but its a lot of load on the gear with the small wheels and relatively long takeoff roll. Any ideas? Perhaps it's just that I need to do like the manual says and just hold the elevator up for the whole takeoff run (feels very unnatural.)
My SB has the regular Duro struts. It used to need a fair bit of steering and careful use of throttle on take offs, but now have a gyro on nose gear, rudder and ailerons. That solved any issues, but I don't often fly from grass.
Question for you, how do the main flex plates hold up to grass operation?
For Essyou, Check this Bandit with a P120. (With wing tanks to add drag) https://www.youtube.com/watch?v=cnYvrLAdNbo