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What do you think of FORMOST 150 ?

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What do you think of FORMOST 150 ?

Old 04-14-2008, 01:56 PM
  #501  
Thud_Driver
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Default RE: What do you think of FORMOST 150 ?

Finally finished up my Formost and put 10 flights on it between yesterday and today.

I did the Cg using scales and as best I could tell it was dead on. On takeoff, the airplane was grossly out of trim. It took 100% up trim and about 40% right trim. After that, it flew very nicely. Roll rate is very good and the airplane does feel good.

I didn''t push it very hard but did do mild loops, Cuban 8''s, 4 points, slow rolls, a couple spins (upright & inverted), etc. In straight ahead idle stalls, my airplane rolls off to the right. The rudders are not very effective. They will not roll the airplane. Trying to do a left spin took forever to get the nose to go left. Knife Edge at half throttle results in a rainbow to the ground.

So, after yesterday, I pulled the 6 cell sub C Nimh battery out of the nose and replaced it with a lighter Lipo - a 7 oz difference just behind the nosegear. The pitch trim went from 100% up to 84% up for about a 3/8" aft change in Cg. Flew about the same and the inverted flight still requires a little more forward stick than I like. So, I''d guess that the Cg needs to be at around 7" back of the LE versus the suggested 6.34". Total weight, completely dry, with the lighter battery, is 17lbs 7 oz. 10 of those ounces came from the foam and tubes I put in the booms.

The only mod''s I did were a full length aluminum main spar (with wood dowel inside), 3/16" balsa shear webs full span in both wings and filled the booms/fins with expandable foam. The wings are still solid after the 10 flights. I am using a single 8411 on the elevator and the ailerons and rudders have DS811's (the ones that come with the 9303).

I have a P-80 (19lbs thrust) in mine since it was the smallest engine that I had. My P-70 is busy elsewhere. This airplane will cruise around all day at a couple of clicks off idle. A P-60 would be perfect. I don''t fly much above about 1/2 - 2/3 throttle. Only a lap or so at full speed and it didn''t seen overly fast.

I made a tank that holds about 104 oz of fuel. After the first flight, I''ve never filled it up again and still go 10-12 minutes with plenty left over.

There is too much residual thrust at idle making it hard to land. A lot like a Roo or Rookie without the speed brake. So I ended up doing a wide low pattern pretty much at idle to kill the speed. If you''re putting flaps on this airplane, do it for the drag. It doesn''t need the lift.
Old 04-14-2008, 02:21 PM
  #502  
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Default RE: What do you think of FORMOST 150 ?

Awesome report thanks for sharing!

-Jorden
Old 04-15-2008, 05:08 AM
  #503  
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Default RE: What do you think of FORMOST 150 ?

My Almost is also back in the running.

After having redone completely the new set of wings (I doubled all balsa wing ribs completely, doubled the wing spar with plywood, glassed + CF''d the wings), I was able to make some three more flights last Sunday in between all the rain showers.
Needs to be rebalanced, left wing seems a bit heavier than the right one so it tends to curve left on idle speed.
You are right, mine floats forever too, making it rather hard to land .

Christos (cairoman) arrived also from Cyprus straight from Amsterdam airport

I have replaced the nose retract unit with a Jet 1A from Digitech. Must say, never seen such quality retracts before and this alu material is very very tough (had to cut off a corner).

The SimJet 1200 SP is also a great match, I think a bit more thrust than the P-60''s, verticals are easy.

I have also moved back the CG a bit, but I did like the flight style more of the first flights. Will measure and share my CG point when I have found the best compromise.

I will NOT stand on the wing -sorry to disappoint you all - I simply do not believe the carbon tube can take such weight now it is completed. The rest of the structure could do it in my opinion.

I also took the rest of Sandor''s Formost kit. Perhaps I''ll do that one with my P-160 and share the wings, just to tease Ali a bit.

The fuel tank is great, I did my first two flights with one full tank only, and Sandor is right, they empty to the very last drop.

Friday I travel to Singapore and will join the Formost pilots there on Sunday... [8D]


Nicolas.
Old 04-16-2008, 04:13 AM
  #504  
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Default RE: What do you think of FORMOST 150 ?

Thud Driver
Since I am doing modifications, should I add a speed brake? Where would it go? Top, like a Hot Spot or bottom like a Roo? Or inboard of the booms with split flaps. I am using a JDE 16lb thrust engine, so I don''t want to add extra weight if I don''t need it. The JDE can be idled down quite a bit to around 40000 to 45000 rpm which can keep the residual thrust minimal. Maybe I just answered my own question. So Far I have finished the wing modifications. Now I will start on the rest. Nothing is hard on these mods, just takes a little time. I like to build anyway and when I build a kit I usually bash them too.
Randy Krul
Old 04-16-2008, 10:20 AM
  #505  
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Default RE: What do you think of FORMOST 150 ?

I''m not going to do it to mine but the easiest thing to do might be to cut the ailerons in half and set them up for Crow. Down side might be the realy nice roll response might go away.

I don''t have a good spot for a real speedbrake so I''ll have to ponder on it for awhile. I''d really want to put it on the bottom, but there''s just too much stuff in the way. Maybe something with air cylinders scabbed onto the sides.
Old 04-20-2008, 02:34 AM
  #506  
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Default RE: What do you think of FORMOST 150 ?

any one can help me ?? i have finished my Formost-150 with jetcat p-60 and its ready to fly but i have one problem.
i think the CG on the manual 161mm its wrong because my plane when its on the floor its going down from the tail ( tail heavy).
did any can help me!!!
Old 04-20-2008, 12:12 PM
  #507  
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Default RE: What do you think of FORMOST 150 ?

Just got back from some jet flying here in Singapore... and two Formost pilots being present !
Thank you, Simon, Jeffrey and Chiimun ! It was a perfect Sunday to me !

They really do fly on an actively used road... no kidding ! [X(]

Nicolas.
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Old 04-20-2008, 12:13 PM
  #508  
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Default RE: What do you think of FORMOST 150 ?

More pics...
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Old 04-20-2008, 12:14 PM
  #509  
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Default RE: What do you think of FORMOST 150 ?

More pics...

And yes, Chiimun flies his Formost with a reinforced wing & long carbon wing tube !
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Old 04-20-2008, 12:20 PM
  #510  
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Default RE: What do you think of FORMOST 150 ?

You can't believe what you are seeing when they fly on this site... but for them it is normal... ! [X(]

Watch this : (Eurosport + PST1300, full throttle between the street poles on an actively used road...) [&:]

One passing van was overtaken by a Falcon 120 at almost full throttle at his window level. Never seen anything like this.
The same plane almost hit a strolling dog on the street when landing.

http://www.youtube.com/watch?v=yZtEIqsSYRs
Old 04-20-2008, 12:21 PM
  #511  
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Default RE: What do you think of FORMOST 150 ?

161mm (6.34 inches or 6 5/16 inches) puts the Cg well in front of the main gear axles. Measure aft from where the stub wing meets the inlet.

If your airplane falls on on the tail, your Cg is seriously off and you need to add a lot of weight to the nose.

Wind has been blowing very hard here so I haven't been able to fly it much. 20 or so flights so far. Going to try flaperons next. Not that I've measured anything but I'm sure the stab is misaligned, plus the flat bottom doesn't help.
Old 04-20-2008, 02:22 PM
  #512  
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Default RE: What do you think of FORMOST 150 ?

Nico,

Sent you a couple of SMS's!!! Anything interesting at rotor????

Chris
Old 04-20-2008, 08:58 PM
  #513  
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Default RE: What do you think of FORMOST 150 ?

Haven't been there yet ! [)]
Old 04-21-2008, 02:25 AM
  #514  
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Default RE: What do you think of FORMOST 150 ?

Here another Formost they were preparing at Rotor Hobbies Singapore, with a JetJoe turbine.
This is already the newer kit, they just received 40 kits in stock.
The major (necessary) improvements are not done yet on this kit version, like the long wing tube and reinforced wings, but the internals looked already much better and were better glued than mine.

Nicolas.
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Old 04-21-2008, 02:28 AM
  #515  
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Default RE: What do you think of FORMOST 150 ?

More...
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Old 04-21-2008, 02:31 AM
  #516  
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Default RE: What do you think of FORMOST 150 ?

More pics...
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Old 04-21-2008, 02:34 AM
  #517  
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Default RE: What do you think of FORMOST 150 ?

... and nose retract, here this one w/ belly mounting.
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Old 04-23-2008, 05:57 PM
  #518  
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Default RE: What do you think of FORMOST 150 ?

flaps came installed on my new wings
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Old 04-23-2008, 09:51 PM
  #519  
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Default RE: What do you think of FORMOST 150 ?


ORIGINAL: idleup1

flaps came installed on my new wings

Yes, I have seen this on the photos they have sent to me from the factory I am not sure this is a temporarily change to the kit or a permanent one... ?
Good thing is they really look like speed brakes in the first place, and that is not a bad thing, perhaps also combined with programmed crow braking.
Nonetheless, I do always like it simple, but this time it looks like such speed brakes are necessary on such floater especially when your turbine has still some quite high idle thrust for this trainer... (=70+ N thrust class)

Nicolas.
Old 04-23-2008, 10:33 PM
  #520  
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Default RE: What do you think of FORMOST 150 ?

I'm using about 75% drooped ailerons as flaperons and it does help a little to cut down on the float. Makes a nice difference in stall speed too. Would have been nice to have had the built in flaps.
Old 05-01-2008, 10:14 PM
  #521  
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Default RE: What do you think of FORMOST 150 ?

Anybody else getting any flights or doing any building, mine has been on hold due to my traveling, I hope to get cranking on it again next week.
Rich
Old 05-01-2008, 10:53 PM
  #522  
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Default RE: What do you think of FORMOST 150 ?

Will receive mine today, see what version that is...gonna use a P80, crow braking is my favorite on many gliders I own, even on a flying wing it works perfect.
Old 05-05-2008, 03:50 AM
  #523  
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Default RE: What do you think of FORMOST 150 ?

Hi Nicolas,

Greetings from Singapore... Thanks for sharing the photos you took while in Sg. I managed to clock in another 3 flights on my Formost last weekend...

Some corrections to your post (#508), I don't use a carbon tube, I am using an extended aluminum hollow tube. Can't find a carbon tube that long locally and to ship in such a long carbon tube would had been too expensive...

For others who might be intereted, the following is my setup:

Rudder and aileron servos: Hitec HS625MG
Elevator servos: HS 645MG
Steering servo: HS625MG
CG: at the location of the aluminum tube (spar), if I am not wrong, my formost is the initial design (same as Nicolas's). I am not sure if they changed the spar location in subsequent designs.
Control surface deflections as per instruction manual.

As for modifications, I only did 2 things. I used one-part PU to stiffen the booms. And I tore out the entire bottom sheeting of my wings to add the following:
- extending the aluminum tube into 2 more bays.
- Adding plywood half ribs to ribs supporting the wing tube.
- Building a box from plywood to enclose the wing tube and capping the top of the box with scrap balsa blocks.
- adding shear webs (vertically oriented grains) to both sides of the wing spar.

I fly with a Jetcat P80 and only on half-throttle except for take-off. The plane will fly even on the residual thrust generated by the P80 on idle... As such, I need to fly a full circuit on idle before making my base turn into the wind with engine cut (manual) and gliding in for the approach...
Old 05-05-2008, 12:45 PM
  #524  
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Default RE: What do you think of FORMOST 150 ?

Since my SimJet spitted long wet flames this weekend while having no fire extinguisher immediately on hand to kill the kerosene having dripped in my fuselage, I have now the very special 'black convertible' version !

High time to apply some high tech Frankenstein transplantation of the other kits' butt plus installing a kerostart JetCat P160 for a serious test.

Nicolas.

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Old 05-05-2008, 01:02 PM
  #525  
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Default RE: What do you think of FORMOST 150 ?

Nicolas, we have a dutch children's song here: wie zijn billekes heeft verbrandt, moet op de blaren zitten....hehehe. (sorry not translatable..)

Good luck with that trassplantation

No time yet to inspect mine, tailbooms feel sturdy, will make pics next week, off to my last trip tomorrow!

Seing those idle problems, it gets time to to get into reversers!

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