Latest project: F-15 Bicentennial

[Warbird]

no problem !!! more pics please

[trailblazer]

[trailblazer]

heh~~

i used the gears meant for an F 18 but wat the heck~~

and my dog got interested in this flying rig and decided that he should be in the photos too so enjoy

lol

[Warbird]

lol (test pilot) !!

Keep us posted on the progress.

[Babylon5]

Hi, nice plane. When and where you guys are maidening these beauty.

Keep us posted.

By the way , for twin the out of balance situation in thrust is not critical like Eric has mentioned the mass or rather the torque arm of the impeller is too short to cause severe torque rolls. If the twin EDF are kept close togather like the SU27 or the F14/15 ,out of balance situation is almost non existence.

Therefore counter rotating duct fan is not necessary.

Note if you must know :Regarding thrust. Two ducted fan running the same rpm do not necessary means both fan are generating the same amount of static thrust. Why, because the gaps between the fan and shroud of each fan may not be the same and thrust are affected by such gaps.

Like I say before this factors are not critical. In my opinion , twin EDF is fun .




Cheers

[trailblazer]

Hi, nice plane. When and where you guys are maidening these beauty.

Keep us posted.

By the way , for twin the out of balance situation in thrust is not critical like Eric has mentioned the mass or rather the torque arm of the impeller is too short to cause severe torque rolls. If the twin EDF are kept close togather like the SU27 or the F14/15 ,out of balance situation is almost non existence.

Therefore counter rotating duct fan is not necessary.

Note if you must know :Regarding thrust. Two ducted fan running the same rpm do not necessary means both fan are generating the same amount of static thrust. Why, because the gaps between the fan and shroud of each fan may not be the same and thrust are affected by such gaps.

Like I say before this factors are not critical. In my opinion , twin EDF is fun .




Cheers

Well... we tend to get picky on engineering flaws don't we?

but we can trust the manufacturers, can't we?

secondly, ur statment is half true... cos you didn't specify the brand and angle of impeller blades.. you didn't specify the setup of the powerplants either so yeah~~

and i agree twins are FuN. Expensive, but FUN

[trailblazer]

oh yah.. before it slips my mind...

how in the world can we counter rotate EDF fans and still get them to push air out the same direction?

Design of the shroud and fan are ONE WAY only so reversing the fan itself would mean you suck at pictorial logic... big time

Reversing the polarity of the motor... can be tried but as above.. the fan thing its linked to the polarity so... BeeP!! wrong

Final option is to mount the fan facing backwards and reverse the polarity... AS LOGICAL as it might sound... there's this tiny problem on the design of the fan blades in the shroud and the shroud itself

see... stators in the shroud "flattens" or straightens out the air flowing out of the fan so there's no vortex that might destabilise the aircraft from there...

reversing the shroud position (front becomes back and back front) would defeat that purpose

next is the fan itself... reversing the polarity of the motor means the fan spins reverse.. think about it, the fan suppose to spin one way only but now its spinning the other way... weird...

unless modellers are asking that a seperate custom fan and shroud be bought that spins counter to the original fan setup

Clarification needed!!

[Warbird]

lol

[TomcatFLYER]

Hi, nice plane. When and where you guys are maidening these beauty.

Keep us posted.

By the way , for twin the out of balance situation in thrust is not critical like Eric has mentioned the mass or rather the torque arm of the impeller is too short to cause severe torque rolls. If the twin EDF are kept close togather like the SU27 or the F14/15 ,out of balance situation is almost non existence.

Therefore counter rotating duct fan is not necessary.

Note if you must know :Regarding thrust. Two ducted fan running the same rpm do not necessary means both fan are generating the same amount of static thrust. Why, because the gaps between the fan and shroud of each fan may not be the same and thrust are affected by such gaps.

Like I say before this factors are not critical. In my opinion , twin EDF is fun .




Cheers

i don't really get torque roll actually, my main balancing problem is trying to ensure both edf produce same thrust so that it doesn;t yaw and roll adversely

[trailblazer]

i don't really get torque roll actually, my main balancing problem is trying to ensure both edf produce same thrust so that it doesn;t yaw and roll adversely

wats the setup??

[TomcatFLYER]

it's not mine, it;s a friend's i was trying his set up

het fans,
typhoon 2w
dualsky esc

i don;t understand why 2 edf side by side can cause torque roll, aerodynamically speaking, the airflow inside the edf doesn't hit any control surfaces, so there shouldn't be a slip stream/ torque roll effect...

[TomcatFLYER]

and having 2 edf side by side should effectively cancel out the torque generated...

[trailblazer]

Typhoon 2W25~!! x2... its here finally...



another image of it



and how it goes with the HET 6904 fan unit

[trailblazer]

My Facebook has more of the photo progress though

Can PM me fro details

[trailblazer]