Greetings,
It appears that the F/A-18 is shipping. It has been a long wait. I wonder if anyone else is waiting to convert this to EDF. I am planning to use 2 midi fans and 930-10s on 22-28 cells motors in parallel. Is there any other setups that will provide over 100 ounces of thrust. I chose the 930-10 combo after reading Chris Trues column on the midifan awile back. Also the fact that the motors can be had at a quite reasonable $125 from hoellin in Germany ( I ordered a slim-50 from them and it arrived in 5 days quite impressive) I will be interested at what else people are planning to do with this kit.

From the chart from Chris True, it looks like 930-10 would be the best choice. I have two midifans with 2 1409/2Y's that I will use with 2 16 cell 2400's in my Airworld ME-262 when it arrives. In my research, i have noticed that the Germans are using the 930-6's also on two 16 cell packs as well. Another choice could possibly be the Schubeler (I know I spelled it wrong probably) fans. They are much lighter and much more expensive. At the recent MWE, there was a set-up in one of the Stoli Migs that used the 1409/2Y and a Schubeler fan with 16 cells that outperformed a midifan with 1412/2Y and 20 cells vertically. My issue with brushless
is finding a speed control that is dependable so a high quality brushed motor might be the way to go. Another question is if the data that Chris True has is applicable to an actual airframe and the variances that may exist in a particular model. Hopefully some useful knowledge will come out of this topic, but there are not many people out there in the U.S. who have tried large twins.

From what I've heard, the Midi Fan is too large for the CBM F/A-18. I was told it requires a 3" fan, eg. HW609, rather than a 3,5". Have you tried to fit in the Midi yet? Did it require any major cutting or what is your practical experience?

Originally posted by PharmD2B:
My issue with brushless
is finding a speed control that is dependable so a high quality brushed motor might be the way to go.

What do you mean? There are some very good BL controllers out there - at a price though..

The CBM Hornet sounds awesome

I know! off the subject but, From the info I have the new Jeti Phasor sensorless cont. will work well with the sensorless motors (Hacker), and at a good price( I think Jeti makes a good cont.). I'll let you know when mine gets here.

Is there any URL to this kit?

THX
jürgen

jürgen,

have a look at http://members.aol.com/cbmjets/homepage/class1.html

--Thomas

Tomme,
Two midi fans will fit but, the rear portion of the fuse would have to be modified to allow for the much larger thrust tubes. Intakes pose another problem, the way the kit is designed the retracts sit in a separate compartment,this means that the fans will have to pull air in over this hump, and will have to sit all the way back in the fuse with short thrust tubes. There is plenty of room for lots of cells. Currently I thinking that the HW 620 may be the way to go. It is a 86mm fan that performs almost as good as the midi fan. I still plan to stay brushed.

Derrek,

Since I've received the F/A18 kit I've also started to look at the HW620. What motor/cellcount combination are you looking at? I was aiming for the HP220/30/A4 S P4 but finding out that this piece would like to run on 24 cells I'm a little worried. 48 cells total sounds ridiculous...

Any other ideas or suggestions? Are you molding air ducts between intake & fan and fan & outlet? I got the intake at roughly 26 cm2, outlet at ~24cm2 but the fan area of the HW620 is 44cm2 and I've learnd that the cross area should stay the same throughout the duct(?).

Tomme,
Im thinking a 930-10 or possibly a HP 290-20-10 on between 20-28 cells. I need to find out how the plettenberg compares to the ultra. I am hoping to see 25 amps per motor and run them in parallel. Chris True wrote an article awhile back that showed the 930-10 would pull 25 amps on 26-28 cells in a Midi fan. The thrust was close to 4 lbs. The HW620 should come very close to matching this performance and a higher exhaust velocity to boot. The advantage of the HP is that is 2 ounces litter and seems to be more efficent.

Derrek

The Ultras are made by Plettenberg, they are identical in every respects once the nomenclature correspondence is straightened out...

Any work on the ducting yet?

Tomme,
I have not done anything for ducting. Im debating just mounting the 2 completed fans intakes and all in the fuse and hope for the best ( the exhaust would be straight out using the supplied cone in place of the foam moulding. Not to glamous but it should work. I'm planning to put a cheater hole in the bottom behind the main gear doors. This may not be the best idea but scale intakes would be difficult if you use the factory retracts.

Herb,
I believe the 290-20-X series is different from the 930-X motors. In plettenberg speak the ultras would be 290-30-X. I was wondering if the Kv's of the two motors were similar.

Derrek

OK. I'll think of that when my fans arrive.

Did you get the scale retracts from CBM? Told me they're not shipping until July... with a backorder queue...

Tomme.
I have order the retracts but they have not shipped.. I would be suprised to see them within the next month. Have you ordered the HW620s ? Im wondering were you got them ,I can not find them in the US.

Derrek