awlaserdesign

we are bussy with the design of the harrier, follow the progress can be here

awlaserdesign

it would be at scale 1/8

BarracudaHockey

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That would be so cool

awlaserdesign

Pegasus

SECRET AGENT

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All electric? No turbine?

awlaserdesign

this one will be electric maybe in future if everything work like we will then we can see what we do but this one will be edf :-)

SECRET AGENT

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Good luck with the project, anxious to see your progress.

awlaserdesign

more 3d printed for testing the Pegasus soon

Halcyon66

You have used my pegasus engine CAD from Grabcad, happy for you to use it yet you should not take credit for the work.

That was first gen done about 6 years ago, did not have good flow and was an initial CFD design test. It was a test unit only and hence the posting to grabcad.

https://grabcad.com/library/pegasus-turbine-1

My latest are much more advanced.

Also looks like you have used,

https://grabcad.com/library/harrier-jump-jet-1, as your harrier and again it is not your work.

Regards,

awlaserdesign

hi halcyon,

i talk to joel the designer of the Pegasus and he told me that he was inspired wih your design but he designed again and modifyd a little, look at the pic:-) alsoo did he make it turnable and also he draw and design the tubes to the end , the nose and the wings

awlaserdesign

if you want i can making contact between you and joel?

awlaserdesign

movements

i wil post video you can see the movements but i must have 10 posts before i can post them , soon you get them

awlaserdesign

and yes the testframe is ready

joel.vlashof

Hi don't worry i wil not use your Harrier for commercial use My goal is to build the AV8 B 2 version/ the dual seat version..longer nose and longer tail for hobby. The model on crabcad, i can not use it for printing parts because its al sheeted. i can not use it to print a plug to do that t i have to rework the complete aircraft. as same for the pegasus. the front section an back section is all redone to optimize airflow. the 4 outputs adjusted to fit thrustbearings..so i did a complete make over.
my goal for now i to build a full scale working Harrier, not a edf drone like vtol machine:P it's my hobby to make molds for making fuselage out of carbon fiber its more fun to help each other

stay tuned

extra 300

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Great Project!! Watching closely, good luck

awlaserdesign

awlaserdesign

new design of pegasus

Mark Powell

The losses on that are going to be horrendous !

Remember, an EDF is NOT a compressor, not ever.

So although your design might look like the full size one it won't work in the same way at all. The full size one had a multi-stage axial compressor supplying the front outlets with high pressure cold air and the 'jet' part supplying the rear outlets with high pressure hot exhaust. Thus, as both the front air and the rear jet exhaust was at high pressure they had a high mass. And thrust is mass times velocity.

But with an EDF as the 'power supply' you don't get any pressure increases, just 'atmospheric pressure' so the mass is low and so the thrust will be low. Even more so when you add in the obstructional losses from the front 'diverters' and the overall high tapers.

joel.vlashof

I know, it is not a goal to compressing the air. I am still searching for the optimum.it has to be scale as possible. big advantage of rapid prototyping..i played for 6 years now with edfs and learned About behavior. See video of my F35... there i do compress air the in 3BSD


https://youtu.be/wliNyVBeczM

Mark Powell

That's very good. You have solved the stability problems too .

But you aren't getting any pressure increase. Not with what appears to be a single stage fan.
You don't need a pressure increase for it to work but that is what awlaserdesign seems to be doing. And it won't work, not with a single stage EDF.
He might not MEAN to compress the air, but with his tapers and small outlets that's what will happen. And it will just stall the single stage fan.

An axial compressor must have a casing tapering from large at the front to small at the rear, and a fan hub of the same length tapering from small at the front to large at the rear holding enough fan stages so that no stage stalls. Without that there is no compression.

It CAN be done with a Harrier. A guy in the UK did it successfully about fifteen years ago. He used two OS 91VRDF glow engines. One used the left intake to supply the front outlets, each half the area of the intake, and the second engine, placed behind the front outlets, took air from the right intake (there is enough space in the Harrier fuselage to do this) and supplied it to the rear outlets.
It had plenty of power for successful VTO but he never fully overcame the stability problems.

Some people don't seem to understand how the Pegasus engine works. It is a low bypass turbofan, with the fan supplying the front outlets and the 'jet' supplying the rear outlets. NOT a 'jet' with four outlets, which is what awlaserdesign is doing with his design. The UK guy, with his two glow engines, each supplying only two outlets, in effect emulated the real Pegasus, which is why his design succeeded. Replace his glows with EDFs and it might work, as, like the real one., the airflow behind each fan will be relatively smooth and unobstructed (no 'diverters' for the front outlets) and the 'taper' will be the same as a simple bifurcated outlet, as used in many EDFs.

Stability:
Provided you can get the 'puffers' to work it is not a problem. It has four. One on each wingtip, which can blow up and down, one on the nose which blows down only, and one on the tail which can blow both down and sideways (for yaw). There is NO automatic stability, it's all manual, though some of the two seat trainers had a gyro on the yaw puffer. This can be switched off and usually is.

I was going to make an F-35. Two 90mm EDFs, one for the 'lift fan' and one for the rear nozzle. The rear nozzle has to bend both from vertical to horizontal and sideways (for yaw) - there is no yaw puffer. Making a nozzle that can do this is not particularly difficult - just copy the principle of the real one (which you appear to have done).
I was going to use small EDFs in the fuselage for the wingtip puffers (which puff down only) with 'flat' rectangular ducts (to fit in the wing thickness) of the full fan FSA in the wing, and during hover mode the aileron stick would be mixed 100% to the wingtip puffer throttles. Similarly the 'down only' nose puffer would be 100% mixed to elevator as would a small throttle mix to the two main fans.
As an advantageous 'side effect', during a 'conventional' landing you can switch all three puffers on at full power with a 'flap' switch. This will perform much the same increased lift effect as genuine flaps but saves the weight/complication of two servos and the flaps themselves.
I drew all this up fully but I eventually decided it wasn't worth the bother and expense. Regular EDFs are expensive enough already (I have several) and other than impressing other modellers for about five minutes we modellers have no 'requirement' for VTOL

The Harrier is not particularly difficult to fly, despite the lack of any stability augmentation. Transition requires some care, you must be going fairly fast to transit from hover mode to conventional mode, fast enough to be at a reasonable 'regular flying speed' or you will lose a lot of height as you transit.
And as slow as possible to transit from conventional flight to hover mode. If going too fast the aircraft will rear up severely during the transition, and to be going slowly (to prevent it rearing severely nose up) in this conventional flight you will be throttled back. BUT - you have to open the throttle quickly as you transit to hover or it will drop like a brick. And throttle response is poor so you have to anticipate.
In hover mode it's just like an extremely stable helicopter.

Incidentally the 'Real Flight' Harrier simulation is good (except that the throttle response is far too fast to be realistic). It seems impossible to fly at first but with a little practice it becomes easy.

awlaserdesign

hi mark,


joel is one my harrier members group , he is doing the great stuf and the beading heart of the harrier , my job in the team comes later when the plane is be build up in wood

regards
wim

Mark Powell

Hi 'awlaserdesign',

I am VERY impressed by Joel's F-35 and I see by his video that the plane is almost complete - it even includes some fuselage frames and a cockpit.
He's done all the difficult parts, tested it successfully, and the rest is just simple stuff which all of us do all the time with a big sheet of paper, a rule, compasses, a pencil, some balsa, some ply, a knife, etc. It's not the sophistication of the tools (computers, 3D printers, lasers, etc. versus a sheet of paper, a pencil, a hacksaw, etc.) you are using that matters, it's what you do with them.

And has he refers to it as "my F-35" I assume he's done it all by himself.

And his F-35 has two fans and the ducting is direct with no obstructions.

Whatever.
I wish you all success, and I suggest you might think about what I said about the UK guy's design, which split the scale intake into left and right halves, put the two entirely separate power/outlet ducting units in tandem and used 'constant cross sectional area' (but not constant cross sectional shape) to provide obstruction free ducting to the rear fan. More importantly, his design also gave a simple 'bifurcated' outlet to both halves.
Totally different from the Harrier ducting as shown, on which the losses will be very high, as I said.

awlaserdesign

hi mark,

his knowledge is verry important and we have 5 people in our team , everyone has his speciality and most important thing is that we al are very good friends

regards
wim

Mark Powell

Good friends with shared interests is important (I got to be a licensed full size pilot that way. And it's how I got to fly a Harrier, even having 'pilot in command' in my logbook, but I never flew it solo. I flew it 'informally' with an instructor on a couple of weekends, when the British RAF shuts down from Friday evening until Monday morning

As for VTOL EDF models I have 'experimented' in a small way but other than the F-35 design on paper I gave up. The 'fun' in modelling is design, build, and flying (btw - ARTF flyers miss out on the first two).
Only the 'design' part is free, the rest costs money. And over the years I have found that building and flying relatively 'conventional' models gives the best value. I have several EDFs including the expensive BVM Electra and a scratch built 76 inch span ME262. But I am coming to think "Am I enjoying this any more than I enjoy a relatively simple F3A aerobatic model?" And the answer is always "No".
Which is why my F-35 never got beyond the 'on paper' stage, though I did design it fully, including the 'puffers' for VTOL control.

And it was the same with my proposed 4 fan exact scale 96 inch wingspan B-2 bomber, which never got past the design stage - in flight it would probably fly exactly the same as a Zagi anyway

erh7771

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Is there a thread the person with the F-35 video is posting on?

Thx in advance