Vettster

I have edited my First post to read..

I have ordered a K100G for this project

edwarda10pilot

My Feedback: (3)

Trev:

PM sent regarding 20 lb thrust turbine.

Ed

Vettster

Did you miss post #50 buddy

I need your input

edwarda10pilot

My Feedback: (3)

Trev:
Are you asking me if the 4" length is sufficient?

Ed

Vettster

Yes Sir. I can lower the nose gear even more..but that means adding blocks as Im sure you use to do on yours. Im hoping that the strut is long enough. But dont tell me what I want to hear.. Tell me the truth

felicitero

The major concern you will have with conversion is strengthening the wings and tail feathers

edwarda10pilot

My Feedback: (3)

Trevor:

My friends F-16 is not handy right now. I can probably get the measurement on the friends F-16 by tomorrow night.

Ed

dw_crash

My Feedback: (6)

There was one experieced job jock here in Alberta that did a F-16 turbine conversion of the Byron kit. He used a PST-600 turbine, the 14 lb thrust version. The model came out a little over 20 pounds. It flew ok. I saw it fly a few times. The main issue was that it did not have a long life. The old polyester and foam technology of the Byron kit just could not handle the stresses of the turbine and weight. Areas like the landing gear, tail mounts and wing mounts just are not strong enough. And, even having added some carbon fibre to reinforce...it was too weak to have a long life. In the end....not worth the effort to make a turbine model.

Between my pal and I, we have had several Byron F-16 ducted fan models. They were OS 91 powered. Once we upgraded to a Hurricane impellor to replace the plastic Byron one....they flew reasonable. Sure they aren't the 200 mph turbine with unlimited vertical. But they fly nice and have a decent life as a ducted fan model.

Best of luck,
DW_Crash

Vettster

Thanks for the input Dave.. But Im not doing this half way. Ive thrown out the original hardware and wont be using any of the original foam. New smaller foam wings and tail feathers on the way that will be sheeted and glassed. Two extra former's have be added to the rear with one more to go in the back. One former has been added up front with another to go. The main former will be reinforced and I have no intention of using the stock gear mounts.(add yet another former) I have no doubt that this plane will be heavier than the golden years.. but it will most certainly fly well with the K100G Im about to order. Ill dial it down a bit to match the planes weight. The motor is small but powerful and only weighs 2.7lbs and 3.5" in dia.

The servos for the elevators will be moved to the rear as with the Rudder servo.

This is probably the biggy.. I dont know if your friend added gear doors...But in my opinion they are critical to keep the fues from ballooning.

The wings will most likely be glued to the fues for added strength and I wont just be adding a little CF hear and there. It will have a second heavier than stock spar add to the front of the wings in place of the alignment pins.

The weekest point from what the guys are telling is the rear fuse wanting to snap off.. Follow the build thread to see how I address that problem...cause I aint trusting just two extra formers to do all the work.

IMO it is every bit worth the effort to make it a turbine.. cause if it we're easy.. I probably wouldnt even bother.

dw_crash

My Feedback: (6)

Vettster,

Moving the servo is job one, even our ducted fan models did this mod. The conversion I saw had the extra formers you mentioned. Further, the bottom Byron cheater hole was filled in and a hatch made on top to access the turbine. The conversion had the orginal Byron foam sheeted then glassed. This worked well and preserves the wing area. Lift comes in handy if you turn into a glider.....

Fixed wings might help in the weight and strength department. The conversion I saw had removeable wings......which do add weight.

You really want to reinforce areas with either kevlar or carbon fibre. The area where you mount and control the stabs. This area fatigues quickly. The other critical areas are the nose wheel and mains. This takes a beating in a turbine version compared to the ducted fan. You may want to consider some structure to hold the nose and main gear to the fuse in a single piece. Maybe some form of stringers to distribute the loads.

Remember....the turbine will be heavier...take off and land faster than the ducted fan kit your starting with. Also, the ducted fan gives 0 thrust at idle. This makes landing and stopping easier. Turbines need brakes to slow down in a reasonable distance. This loads the fuselage. This is where the fatigue of the polyester really shows....

Good luck, fill us in on the life cycle of this jet,
Dave

Countryboy

My Feedback: (25)

The stab modification for the ducted fan version was simply an extra former with a servo mount keyed in between it and the original former. It was configured so the servo was placed inside the shelf on each side. A direct link was then made up which dropped through a hole in the bottom and was attached to a ply rib epoxied to the root of the stab. ABS covers were supplied to cover the holes cut in the shelfs to access the servos. The original stab servo location is perfect for the fitting of a rudder servo.

Vettster

Thanks for the info guys.

Dave its like your reading my mind You are pointing everything that I intend to attack. The CF in the stab areas I did not concider. Ill incorperate that into the master plan.

Thanks for the photos Cowboy.. I have a slightly different aproach as in the photo ive posted.

As for strengthening the fuse even more.. I intend to box in the sides of the fuse. This will greatly improve structural strength down the entire fuse. Im refering to the fuse are that starts to become wing. The wing root on the real plane.

I still have lot of extra former's to add.. the nose gear being one of them. The mains gear will be mounted on 2 one piece formers.(I cut them tonight)

Not to worried about the landing speed Dave.. I couldnt be harder than the F-104 with its tiny wings.

Here's the maiden of my PA F-104. The ailerons where super sensitive so I took off and landed it quickly
http://www.youtube.com/watch?v=99MfLwftw7c

edwarda10pilot

My Feedback: (3)

Trevor:

Looks like work is progressing very well on your F-16. I got out to measure the Byron F-16 EDF model and here is what I have. Distance from bottom of fuse to ground on nose gear strut/tire is 5.5 inches. Distance from bottom center of fuse (between the main wheels ) is 4.5 inches. Nose wheel/tire is 2.5 inch diamater and the mains are 3.5" diamater. You might consider lenghtening the nose strut about 1/2" and then setting the main gears for about 2* positive AOA. I am going to look around and see if I have a plastic model of the F-16 and see what the scale gear length is compared to the Byron model. I will post if I have any additonal data.

Hope all of you rang in the new year in a safe manner and wishing all a happy new year.
Ed

Vettster

Thanks for troubling Ed!

I have had to add the blocks to the nose gear. It is now 5" from the belly. In the early post on this thread and from Vids Ive seen.. This puppy really sits nose high on the ground. I will do as you mentioned Ed and aim for a 2* angle of incidence.

Been sick as a dog that last couple of days and now its time to go back to work! Ahhh

I was last working on getting rid of all the silicone that previous owner has applied to the main former. One side at a time and then hysoled in so that it doesnt move.

Vettster

Something else that I feel needs addressing is the way the canopy sits on the Outside of the plane. This might have been ok for the slower ducted fans.. but I fear that over 150mph the wind would get under it and rip it off. I will see if its possible to mount the canopy from the inside and secure it in a way that it can be removed.

dw_crash

My Feedback: (6)

Neat StarFighter.......looks hot!!!!!

I didn't intend to comment on your skills.....just the airframe's ability to absorb flight and landing stresses. I know your thumbs are first rate!!!!!

Dave

Vettster

Its all good Dave. I never took it the wrong way. Thanks

skyhawknut

My Feedback: (3)

the way the canopy mounts is only half the problem. You can change the way it mounts - but then the problem is material thickness. I've heard where some have started to deform and collapse inward as they are not strong enough. Since the F-16 has very little bracing in it's canopy - the only option to stay scale is to mold a new one from thicker plastic.

Vettster

Thanks Shyhawk.. Cant say Im happy to hear that news[]

I wasnt planing a scale paint scheme anyhow... So It looks like a dark tint is in order. Ill add structure to the inside.

The guy I bought the canopy had ten. I think he might have had them made out of thicker plastic like you said as an upgrade. It does seem to be rather heavy/strong.

Something to think about

edwarda10pilot

My Feedback: (3)

Trev:
I agree that the canopy mounting needs to be modified. The one we are flying has not been modified and is simply held on with four screws thru the canopy and the fuse into some small ply squares glued into the inside of the fuse. The blue and yellow model has the pneumatic retract filler valve and the rcvr on/off switch on the external part of the fuse so there is no need to get inside the cockpit. There is probably a neater/better way to do it but we did not modify the blue and yellow one I sent photos of. Might consider some sort of inner structure in the fuse to strengthen the fuse as it is the weak area. When you said you might consider tinting the canopy, I will say that years ago I had two Y/A f-16's and the second one I used a "Ritz" brand dye to tint the canopy. If you look at some of the full scale F-16's they appear to have some sort of protective coating on them that makes the canopy have a bit of a gold or copper like tint or look. When I dyed my canopy, I used Ritz yellow dye to try to get a bit of a gold or copper look to it. Might try something like that on a test piece or old canopy.

Ed

Vettster

Thanks Ed. That blue/yellow one looks like a nice clean build and should be very easy to see in the air. Thats your buddy's right? I forget if you mentioned or not...Do you still have one?

I will be reinforcing the canopy.

edwarda10pilot

My Feedback: (3)

Trev:

The F-16 is my friends and is the one that I painted and did some of the fabrication work on. It is the colors of an F-16 squadron in Houston Tx. The color scheme was one that commemorated the 90th anniversary of the 111th Pursuit Squadron in Houston, TX. The color scheme was one that used the colors of the squadron in the 1920's. See link below.

http://www.f-16.net/units_article42.html

I no longer have the Byron F-16. I am currently working on a Byron Mig that will have a Byron fan using an HET 800 series inrunner. It will be an EDF. The first Byron EDF conversion I did is on the Yellow/Blue F-16 in the photos. The system puts out 16 lbs of thrust, 4.2KW of power on 12S at 94 amps. This combo is turning the stock Byron rotor at about 23-24K rpm. Efflux is about 170 mph. Plane weighs about 14 lbs AUW and it flies very well on this setup. I would estimate the plane speed to be about 100 to 110 mph.

Ed

Don Y

I have converted the Byron F-16 to turbine using an old 750. Weight was not a problem. Biggest problem is very little room near CG for fuel. I used wing mounted drop tanks with shampoo bottles for fuel. Worked well even with no baffles in tanks. F-16 flew well without ailerons. Good luck, Don Y.

Vettster

Good Stuff Ed. Though with an eflux of 170mph.. you might be suprised to find your doing 140-150is. Put a GPS on her

Vettster

Hi Don! I sure hope you have plenty of photos and video to share[8D]

I like the idea of the wing tanks as a fuel tanks..

Really would love to see photos of your mods.

How many flights on it as a turbine

Trevor