Dave Wilshere

I don’t know KingTech motors, but if that is a small case motor then you wont get the best performance, you would be better off with a Joker

Dave

peter 098

Do you know of any company that sell a trust pipe that would fit the ultra flash and would work with the 80 size turbine?

Dave Wilshere

Grumania in Germany

Dave

peter 098

Ok thank you

peter 098

One more question, how long is the tail pipe in the ultra flash evo?

peter 098

And what are some of the dimensions of the pipe?

Dave Wilshere

I’m in Scotland just now, but Grumania will have the sizes if you order from him

peter 098

Ok, thank you for the info.

peter 098

Can someone please tell me the length of the tail pipe with the entry cone? thank you

Dave Wilshere

Tailpipe is 485mm. Outer cool wall projects 8-10mm more. Cone is 75mm long

peter 098

Ok thank you

Mi-25

Hi Dave: I have a query concerning the fact that you've mentioned a few times that the UFlash requires Down Elev trim with FULL FLAP. Firstly, did I understand you correctly ? As a long time full size pilot (and also modeller) when the aircraft is slowed to approach speed with full flap extended UP elevator trim is usually needed to balance the nose drop (we need to forget the fact that many model pilots select initial flaps at too high a speed causing a 'balloon' requiring Down Elev).
Secondly I'm curious as to why the UF requires down elevator trim with Full Flap? This must be due to a quirk in it's aerodynamic properties I imagine. Lastly, does this down trim condition change with reducing airspeed?
Sorry for all the questions: I set my full flaps to 105mm as you advised. I'm unsure what the intermediate setting measurement is - so I've eyeballed it.
What I'd like to know is how much down (mm deflection) is required on the Elev Trim?
thanks,
Leon

bodywerks

My Feedback: (4)

I can say without question that DOWN elevator is required with ANY flap input on this aircraft. In fact, what they recommend starting with is not enough in my experience.

bodywerks

My Feedback: (4)

Every aircraft is going to be different, as far as aircraft design goes. Some might require up elevator but in my experience the vast majority require down.
I work on bombardier CRJ aircraft and Embraer aircraft for a living. Both automatically change the incidence of the stab with flap input, positive incidence(down trim).
the Ultra Flash has a manual. Whatever it recommends, which is an amount of down elevator, add a millimeter and go from there.
You are right, there is a ballooning effect if you overspeed the flaps, and can make flap/elevator mix quirky. But once you get to short final, it's all personal preference. Some like to fly to the runway, cut throttle, and then flare. Some like to maintain a slightly positive aoa and modulate throttle all the way to ground effects and then cut throttle and land.
Adjust to your landing style.

causeitflies

Personally, I have only flown one model jet (Hunter, split flaps) that didn't require some down trim with flaps.

Dave Wilshere

Leon

Yes, down is required, at 105mm 4.5-5mm measured at the tip of the elevator. Balance position will change it a tiny bit.
Generally down is needed, Up on BobCat/KingCat. Normally nothing on split flaps or properly designed Hawks nothing is needed. It’s all aerodynamics that dictate this, tail height, incidences, etc

Dave

Mi-25

Thanks for that !

Mi-25

Again, thanks for replying...

Mi-25

Thanks for that Dave - I'll set it up as prescribed...

bodywerks

My Feedback: (4)

That might be where I went wrong. I don't think the manual stated "measured at the tip". I started with 5mm measured at the root.

Dave Wilshere

At the root it’s nothing like enough! Pretty certain I wrote at the tip...it’s the only reference datum.

Dave Wilshere

The flap settings for the Ultra Flash are:
The Ultra Flash requires down elevator with flap. Take off 1.5mm and Landing 4.5-5mm measured at the elevator trailing edge tip. Exact figures will be affected by balance position.
Movements ailerons 15mm up and 18mm down-Expo 35-40%. Elevators 15mm up and 16mm down 45-50% expo, Rudder 45mm each way 30-35% expo. Ail/Elev tip joint. Rudder lower TE point.

Yep, what I wrote in the manual 🙂

Didier

Hello Dave,

Maybe it is already asked, I don't know but do you known if the new EVO fuel tank (3,5l) fit the "old Ultraflash". I can image that you have to sacrifice a part of the inlet duct and by-pass.
I am getting tired of the the "2 fuel tank system" and this looks like a great solution.
Do you know if this fuel tank is in stock in Europe.
Thanks

Brgds Didier

Dansy

My Feedback: (53)

Dave said earlier that it was the same fuselage.....so it would fit taking the bypass out and perhaps having to cut the intake a little like in the EVO fuse...I think they are a little shorter.....but it would fit for sure..

Dave Wilshere

Yep, tanks in stock in Europe. Fuselage is the same, cut back the inlets, modify the tank mount and fly