Did Some nose work on the Hawk today.

No worries on ESC 250A Unit. Big thing about Schubeler is they know their stuff! 4 of these TP G8 packs give me 14s and 10,000mAh. ESC is never the worry, motor temp is everything. In developing the Spark I only blew motors...which took out the ESC each time. The guys in Germany fixed it soon enough.
No inlets, the inlet lip will smooth out air going it. I'm opening up everything for air intake, mainly on take-off. I can get the outlet within 5mm of what we want for the DS94 by removing the small lip at the back.

Dave

Hawks. Fuselage and tail (just less wings) one with empty main tank balances at 208mm and one with 1/3 fuel in main tank is 192mm

Dave

Very interesting. Mine with UAT full, tank empty and nose gear down, is at 158. I would ay that is very nose heavy. Do not know how I got there. Explains a lot.........

That would make the balance around the same place, you must have more that 4.5mm from the underside of the tail to split line!? The customer bought in the model I'm to test fly...overly complicated install and way heavier than my model. Though today I heard of a near 40lb version and that flew shi*e
Both mine were gear up.

Dave

That is with the wing off. Yours was at 208 and mine is at 158.....Its about 5mm ahead of the panel line. Makes it very nose heavy......

Nose gear up makes about 1.5mm difference.

With the recommended elevator throws, anyone seem to need a lot of down elevator to maintain level inverted flight?

Thanks Dave, 208mm, empty tank, nose gear retracted for a fuselage only CG. That will save me a bunch of time and frustration Monday!

I have between 4 - 4.5mm when trimmed for level flight.

Busy day at our local patch, I've test flown three new Turbine models, FL Hunter, an UF and this CARF Hawk. Smiling Matt after the first flight, the conditions today were rough with a tonne of roll over from up wind ridges and gullies. This Hawk was hugely nose heavy too, we added a few hundred grams of lead to the tail and moved the three packs back and its still infront of where I'd like it. Even so landings were fine using a burst of power at touch down. XG-11, P-140Rx M&R spec accessories.
Matt had a fly around, second flight and loved it. Needs some serious re-installing to sort out the balance before I finish honing the set-up


Dw

Does yours climb with power?

mine does ive only got a cpl flight on it but ill dial it in and maybe move turbine on the mount ill see

kevin

I dropped my engine below the rails and adjusted the pipe appropriately but it still climbs some at full throttle. Less than it did before I moved the engine higher. Will probably mix it out. Will probably add more down elevator throw in general so inverted flight is easier. I'm around half stick to keep it level at medium speed which is very uncomfortable.


Dave, since you've flown so many of these, when one is nose/tail heavy is it obvious through the turns that it noses down/up respectively or does it stay mostly neutral and only shows when landing? Thanks.

Matt, black scheme looks good...

main fuselage painting is complete, so decided to make a set of new strobes (have cut the reflective tube different on this set which makes them a bit brighter than the original ones that I made (not that you could not see those) then I can start putting back the tube and turbine
Last pic the bright led caused the iPad camera to close right down, but up close about a couple of flashes is the most eyes can take before going wonky!

Alan

ps RCU slowly getting better, I found if you add pics with cursor after your last words then it will add as you can see here but if you have cursor in middle of text then your pics end up in that line of txt if that makes sense

Hey guys I though you might like this I filmed a beautiful Hawk this weekend and even got my go pro into the cockpit check it out tell me what you guys think
http://www.youtube.com/watch?v=fhsAs2AxcfU http://www.youtube.com/watch?v=nWWlog3eYJg

As usual, beautiful work Alan.

Speed dependant, flying slower it does drop its nose in turns, tail heavy it sits down on its tail in turns and "digs" in a bit. My standard balance check is a slow-medium roll, if you need lots of rudder and down during roll , its nose heavy. My own Hawk only requires a little of each during rolls. Never completely neutral, its no pattern plane. KE also normally can be done at medium speeds and not more than half rudder. Mine will climb in KE without full power.

Matt's Hawk today was at least an inch nose heavy on first flight as we ran out of weight to add right on the rear face! Was windy, but landing was still on mains with nose up. Just needed full up and a burst of power as it flared. With the drag available power is on even on the approach.

Dave

Yeah, I think my CG is good. Just measured elevator throw and I was a few mm short of the recommended 25mm down so upping that should make inverted somewhat easier.

How the Heck did his Hawk end up so nose heavy? I thought they need nose weight? I am anxious to check mine now. Got supplies from Dreamworks today, 2 days from FL to CA, gotta love Priority Mail.

The manual gives a pretty wide range for expo, I know that is largely personal preference but this is my first "flying stab" not counting gliders. Do they need any special setup consideration? And would you guys say the manual throws are high rates or low rates? Also with JR I can set the trim steps, 4 is default for first flights, but that may be too coarse for a jet? I know it is all personal preference and I will get it dialed pretty quick but it is my first jet so I thought I'd ask...

That's what I thought while putting mine together but upon balancing, I had to move my ECU battery from mid cockpit area to on top of the fuel tank. Depends a lot on your cockpit setup.

Husafreak, have you some pics of your install?

I remember on my Hawk the first two flights that Dave did for me I had around 50g of lead in the nose, once I fitted the Der jet cockpit on with one pilot I had to remove all lead weights out of the nose and I had to fit 10g of lead right at the very back of the fuselage but on both configurations the Hawk flew level.

As others have said this completely depends obviously on what and where you have put equipment. I had two A123 up front either side with the JC LiPo up front with the NAV light Li-ion up top over C of G

Alan

Cockpit and install, when I designed the tray and wood if was for a 400gram cockpit and small TP Rx Li-Po packs. Matt's model had big Rx packs on 6mm ply supports either side of the nose unit! heavy pilot,
Turbines vary in weight, tail servos. I always bolt in the fixed position stuff and move around the batteries-heavy bits. Again, Matt has smoke pump, lots of heavy "bling" (two ball-valves AND a Festo quick connect for filling)

The EDF Hawk I've fitted the tail servos, making the cockpit canopy, fitted the fan, will make up the tube and then work out battery position...

I was able to get the fuse to balance at 208mm back from the bulkhead (LE of wing assembly) by putting the Cheetah's battery against the main bulkhead at the back of the cockpit and the two 2300 LiFe Rx packs just in front of the electronics tray. This is with the DerJet cockpit tubs but not the BVM pilot... I am using the stock pipe and the Cheetah, which is a light engine, smoke tank below the main tank. I did the two door nose gear instal so that added a bit of weight up front. So I have to get the pilot figure as light as possible but ultimately I might need to move all the batteries to he bulkhead. I don't like the idea of mounting the batteries on the fuselage sides but it is an option. Anyway CG is really close so I am pretty happy! I have all the plumbing in and the EV5 works the gear and doors like a charm. I put two of the large Robart air cylinders in above the main tank, the EV5 uses one for brakes. Just need to secure all the bits now and it will be go time.

Looking back thru the thread we have the manual CG at 190mm main tank empty UAT full. But some have moved it back to 195 or even slightly farther back (this with wing on). Do you still recommend 190? I don't like nose heavy planes.