Solomon's home built ultralight

[solomon]

Hey guy Solomon here, some of you might know me and some of you might not but I’ve been working on this little plane for about 2 years now not much work is left and I’m up to the all-important weight and balance. It's tricky getting a plane that weighs around the same as the pilot to be well balanced during flight, and so I was wondering if anyone knew where the cheapest place I can get a recovery chute, the lowest I found was $700 on eBay but I can’t afford that right now. I would also like to know if there’s any chance of my plane getting a registration, because I heard the inspectors can be very picky over things. It would be great help and muchly appreciated if you guys can help me.

 

 

I'll keep you up to date soon with some videos.

 

 

[aaron roberts]

What engines are in that thing?

 

 

[winsor68]

You have some flying experience now... what is your impression comparing your aircraft to the Jabiru you flew?

 

 

[solomon]

You have some flying experience now... what is your impression comparing your aircraft to the Jabiru you flew?

Hey winsor68, the jabiru that I flew felt like are very stable plane and their not very sensitive either but their good fun. Whereas mine even though I haven’t flown it yet I know the pitching is going to be very sensitive since the tail is short and also I’ve also noticed when I was taxing up down the ruder pedals which also controls the front nose wheel is extremely sensitive if you over correct during take with them pedal it will be trouble. So yea... when I sit inside my plane it feels allot different to anything I flew before because of it size and layout.

 

 

[winsor68]

Have you done any sort of load testing on the mainframe?

 

 

[solomon]

Have you done any sort of load testing on the mainframe?

not yet, but I'll get to it soon.

 

 

[solomon]

What engines are in that thing?

I modified two high performance chainsaw engines they give a total power of 8.2hp

 

 

[fly_tornado]

do you have dual throttles?

 

 

[Hongie]

Can't register twin engines raaus? Could be wrong

 

 

[Guest ozzie]

Solomon what capacity and brand engines/ props? I run two 100cc Pioneer chainsaw engines 5.5 hp 35lb thrust each.

 

As for the BRS, they are expensive and heavy, maybe you should call into a drop zone and find a rigger or the Chief Instructor. You maybe able to locate a usable round reserve canopy and a suitable container/ harness. I use one of my old rigs and round canopy. You could also plead your case at www.skysurfer.com.au

 

Enjoy your test flying.

 

ozzie

 

 

[dazza 38]

The engines look like Stihl in the photo.

 

 

[J170 Owner]

Hells Bells Solomon - I wish you luck. Wear a crash helmet on your maiden flight!

 

 

[solomon]

It's a single throttle for both engines. I estimated that the cruise speed will be 80-90km/h, stall speed 55km/h or possibly lower if I make modification to the wings and a VNE of 105km/h. My engines are both a baumr 62cc engines 4.1 hp each revving a maximum of 11'000 rpm with no load and spinning 24 by 16 inch menz wooden props. I’m not sure how much thrust they produce but when they’re both running at full power they can push really good! I was also thinking of getting recovery chutes for Para gliders since they are allot smaller and lighter and can carry my plane at gross weight of around 160kg.

 

 

[Guest ozzie]

I would recommend that you have two independant throttles. It is doubtfull that the engines will run at exactly the same rpm so you will need to 'sync' them to stop yaw. assymetric use of power is also handy on the ground for tight turning.

 

 

[solomon]

I would recommend that you have two independant throttles. It is doubtfull that the engines will run at exactly the same rpm so you will need to 'sync' them to stop yaw. assymetric use of power is also handy on the ground for tight turning.

Yea that is indeed true, but some told me that I wasn’t allowed to have a dual throttle on an ultralight, because if you have twin engines on an ultralight they must be under one throttle control so that they count as a single engine.

 

 

[Guest ozzie]

Solomon make sure you always check the regs yourself. There are at least 3 twin engine Lazairs on the register and there have been other changes regarding recently. A quick phone call to Steve Bell at the RAAus will sort it all out. If you were only allowed one engine, fitting a single throttle won't get around that rule.

 

 

[solomon]

Hey mate, I posted some where else about using my trailer to get your aircraft to an airfield some where, the offer still stands. I have lent it to another fella and it should be back in Vic at the end of Februarycheers Mat

Ok thanks for that I'll let you know when I need it.

 

 

[solomon]

Solomon make sure you always check the regs yourself. There are at least 3 twin engine Lazairs on the register and there have been other changes regarding recently. A quick phone call to Steve Bell at the RAAus will sort it all out. If you were only allowed one engine, fitting a single throttle won't get around that rule.

Ok, I'll be sure to double check that.

 

Thank you.

 

 

[Deskpilot]

Solomon, I've got a feeling your aircraft will be to heavy to fit into the category that allows 2 engines. Be prepared to have it grounded. Mind you, if it were, and I was you, I'd still be tempted to try a 'pigeon hop'. But that's me and I'm not saying you should try it.

 

 

[eastmeg2]

Hi Solomon,

 

Have a read of CAO-95.10

 

If you can have the sum of the aircraft, yourself and fuel (ie, everything) come to less than 300kg then it fits within the weight limit. There is also a 20kg allowance for a recovery parachute which bring the allowable weight up to 320kg.

 

That said though, if your horizontal stabiliser is too close to your main wing then pitch stability could be a problem. Same for Yaw and vertical stabiliser.

 

Easy fixed - replace it with a trike wing :roflmao:SORRY!!!

 

If you do manage to get it off the ground with 8.2hp be sure you're aware of the difference between being in "ground effect" and really flying at more than a wing span above the ground. Wouldn't want to run out of runway and not be able to climb out of ground effect due to insufficient power and not have enough space to land and stop.

 

Not much point having a parachute (extra weight) fitted at that stage of testing since you need at least a few hundred feet between you and the ground for it to be able to do its job.

 

Cheers,

 

Glen

 

 

[solomon]

Solomon, I've got a feeling your aircraft will be to heavy to fit into the category that allows 2 engines. Be prepared to have it grounded. Mind you, if it were, and I was you, I'd still be tempted to try a 'pigeon hop'. But that's me and I'm not saying you should try it.

Hey there, I forgot to mention my gross weight at take including me and a full fuel tank is just about 150kg, the plane looks allot lighter than it looks.

 

 

[solomon]

Hi Solomon,Have a read of CAO-95.10

 

If you can have the sum of the aircraft, yourself and fuel (ie, everything) come to less than 300kg then it fits within the weight limit. There is also a 20kg allowance for a recovery parachute which bring the allowable weight up to 320kg.

 

That said though, if your horizontal stabiliser is too close to your main wing then pitch stability could be a problem. Same for Yaw and vertical stabiliser.

 

Easy fixed - replace it with a trike wing :roflmao:SORRY!!!

 

If you do manage to get it off the ground with 8.2hp be sure you're aware of the difference between being in "ground effect" and really flying at more than a wing span above the ground. Wouldn't want to run out of runway and not be able to climb out of ground effect due to insufficient power and not have enough space to land and stop.

 

Not much point having a parachute (extra weight) fitted at that stage of testing since you need at least a few hundred feet between you and the ground for it to be able to do its job.

 

Cheers,

 

Glen

Hey Glen, yea mine will fit under the category since is half the allowance limit, but I’m thinking of expanding the tail section out a bit more for better stabilization and as for the power you can pretty much fly with any engine so long the wings produce the lift needed from what the engines are giving out. This plane won’t be going anywhere until I think it has a good chance of flying properly and safely!

 

Thanks Glen.

 

 

[motzartmerv]

G'day Solo.. Make sure you get someone else to have a good look over it before you attempt a flight. Several someone elses would be better. It will need load testing and various other things before you can even contemplate a flight. Make sure an engineer (not just a level 2) "thinks" its ok first.

 

(get your chief to call me again, Ive lost his number)

 

Cheers mate

 

 

[solomon]

G'day Solo.. Make sure you get someone else to have a good look over it before you attempt a flight. Several someone elses would be better. It will need load testing and various other things before you can even contemplate a flight. Make sure an engineer (not just a level 2) "thinks" its ok first.(get your chief to call me again, Ive lost his number)

Cheers mate

Hey Andrew,

yea I’ve had a few engineers come along and look at it and they think it's great but I need to get ones who work with ultralights, and I’ll be sure to complete all the on ground testing before the test flight. (I’ll also get Bruce to give you a call)

 

Thanks Andrew.

 

 

[sain]

Hi Solomon,

 

I like the concept of your aircraft, but as the others have mentioned it looks really closely coupled to me.

 

You'll need to build yourself at least one other wing to do the load testing on. I've never done it personally, but most of the photos I've seen of the process end up testing a number of loads (i.e flight loads @ 1G, 3G, 6G), and then continuing until failure.

 

There are some nice pictures of the Xenox undergoing its stress testing here:

 

http://www.sonexaircraft.com/aircraft/xenosdev/xenosarchive3.html

 

I'm also curious what aircraft design and/or engineering books you've got access to? I'd like to send you a copy of a couple of the books, but I want to make sure you havn't already got them.

 

I was thinking of sending Raymer's Simplified Aircraft design for homebuilders and his Aircraft Design: A conceptual approach. Anybody else got any suggestions for good books?