Low draw, longer flight, less weight and more fun?

With the 4800KV 20A brushless the flight time is only 4 mins, with the EDF55.
I have no idea what a 4900Kv 10A brushless with a 50mm EDF would be like. Reviews have said that the 4900Kv puts out 540g of thrust, but thats with no information on ducting etc.
Will the lesser Amp requirement from the 4900Kv provide more flight time, with the same thrust output? we'll have to see..

I also found some EDF Facts which is a very interesting read. And i picked up some pointers on ducting and intake rings which i didnt know before. And also a DIY Intake Lip

1st Dev Maiden

Weather was perfect, blue sky and a slight breeze.

Airframe - Tomhe Quick build Eurofighter.
Power - 4800Kv & EDF55
Fuel - 3S 1300 Mah

Total weight = 450 Grams / 1Lb

Without any equipment to measure thrust, im judgeing by sight and feel alone.
The EDF55 is unducted, and just mounted into the airframe.

Hand launch was fine, 3/4 throttle and then full on releasing it. It was an under arm throw, and not much effort went into giving the airframe any momentum. However, she took to speed well, and began to climb. In comparison to the 6x4 prop power to climb was slightly down. However she was able to climb quite well until a docile stall, controll was easy to pick up again.

Battery only lasted for seemed like 3-5 minutes compared to 9-11 minutes with the 6x4 prop setup, however i am encouraged the power setup of the 4800Kv will be fine with some duct tuning!! I was able to fly comfortably on half throttle on the second flight after a change of battery.

Now, the next stage will be ducting the single EDF, and getting another to match it. Total weight including Lipo will be 640 grams approximately. And with a claimed 500+ gram thrust with x1 EDF55 with a 4800Kv should hopefully see 1KG of "claimed" thrust.

This was more of an EDF leap of faith, from prop to ducted fan. Im sure a 4400kv motor would run more efficently, however i cannot locate a cheap enough motor as the 4800Kv. Now that i am confident with both the airframe and the EDF unit, its time to develope the Tomhe design as a foundation for the full fuse twin EDF.

Profile to EDF full fuse

EDF55 & 4400KV

http://www.rcgroups.com/forums/showthread.php?t=671324

Based on my experience with that fan, the 2030 3500kv motor you suggest would
give poor performance. If you don't want a lot of thrust it might do, but I
estimate you'll only get about 200g of thrust.I tried the 2040 4800 kv motor
from uh in the fan and it give lots of thrust (500g+) but the amp draw is a bit
too high (28A) The motor could hold it with a heatsink and thermal paste applied
(AND cooling after flight to avoid heat soak) but it's really pushing the
limits. Recently I purchased a HXT 2435 4400 kv motor for the fan and this is the
way to go I think. The motor fits the fan and supplied adapter (2mm) perfectly
and produces 370g thrust at 17A on a 3s lipo. Don't mind the advertised 3mm axis
on the motor, it comes with a 2mm axis (UH have strange measuring tools)

The Tomhe Quick Build Eurofighter weighs in at 400g (without a 3S 1300 Lipo), it currently has a 4800KV motor. I installed this into my Tomhe Eurofighter replacing the 6x4 2200Kv prop pusher. A few static tests show that the plane will push itself vertical from standstill. However i am concerned with blowing the motor if it gets too hot (See above quote). IF this setup manages to fly i would like to twin the EDF setup, seems much better to have x2 exhausts, than 2 for looks alone (and sound). Much like the pusher prop setup, there must be an ideal KV for a EDF55, and so far 4400KV seems to be the only thing close to it, but a few flights with the 4800Kv and we'll see the results from it.

Eurofighter 29" Project

Euro fighter Full fuse plans A4 tiled
2D Image

For the last month I have been flying a Profile Pusher Eurofighter. The plans came from http://rc.tomhe.net/eurofighter
This has been my first successful flying plane from a scratch DIY build with depron foam. I have attempted the F22 with vectored thrust, but for one reason or another the plane was uncontrollable. However the EF2000 took off striaght from my hand without complaint.
Building on my experience of the EF2000, I am hoping to build the plane again with a full fuselage. There are two options. One is as above to the same scale as the one I am currently flying, or, http://www.parkjets.com/ef2000-alan.html
I jumped from one design to an EDF 21" wingspan, however, I did not check the CG on the full fuse EDF version on BigglesJet's plans, and ended up only having salvaged the top fuse. At some point I will try and rebuild the main wing and intake again. http://www.rcgroups.com/forums/showthread.php?t=438680&page=11

Ideally i would like to have a 21" aircraft for the back seat of my car, but the 29" so far, has a very stable and robust airframe to fly against mild windy weather.