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Old Sep 11, 2012, 02:15 AM
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Hi Pulser, great F-100 you have there ... there's several at my field and they fly well.




Hi Graham, here's my very personal opinion

Pros of FlyFly Hawk : Inexpensive, very light and therefore potentially very aerobatic, presence or size, great flier (very good wing design), easy to repaint, takeoffs on grass no problem, easy to build, everything fits well out of the box, many similar airframes to move the power system in, easy to work with since it's large, retracts and struts are cheap and fit right in with almost no mods, ideal edf jet to test different power system, plenty of space for batts etc.

Cons of FlyFly Hawk : Foam dents easily, this is a one-season semi-disposable airframe, the finish is foam so it's not shiny, deep ridges, it's big (draggy) so it needs quite a bit of power to fly jet-like, retracts and struts are a bit flimsy (depends on how you land), foam can be weak (possible structural issues).

Pros of CMP T-45 : Great scale-like looks, can be improved to a point where it looks really scale, including scale struts, cockpit with detonation cords, scale pilots, great decals and finish, wont'scratch easily, sleek design offers good speed (low drag), solid rigid wing and empennage, linkages are tight and solid, very little hangar rash, won't dent / crack easily when you put it in the car etc.

Cons of CMP T-45 : Heavy, high wing loading is ok for speed but not necessarily for aerobatics, risks of tipstalls on takeoffs, maneuvers & landings, small airframe with tight fits of everything, visibility issues since it's smaller, components are packed and crammed in fuse, fan is a tight fit, everything has to be laid out properly and trial fit otherwise things will not fit, lands harder on gear which needs to be stronger to take the punishment, might need asphalt runway etc.

.
Herb,

Thank you for your comprehensive response.

I have a few FLYFLY kits that I have now flown and love them. I am however looking at perhaps flying a composite too, but on the Hawk there seems to have been a few issues with "survivability" and wonder if it is more a kit issue or competancy issue upgrading to more jet-like fligh characteristcs.

The Viper also seems to be a good buy, but we cannot get it here due to HK not exceeding certain postal sizes.

Regards

Graham
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Old Sep 12, 2012, 03:32 PM
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Hi Graham,

I think it is more a "large lightweight foam" vs. "small heavy composite" issue ... As far as I know many smallish composite china-made edf jets suffer from the same problem (CMP, JT, proedf etc.)

In the old days some edf composites were very light, and a work of art in fiberglass-airex-sandwich construction (eg Aeronaut Panther, Aeronaut Rafale, JePe F-16, WeMoTec MiG-15, JetArrows Vampire, RD El Bandito, Scheubeler Hawk, K&A etc.).

Recently some of that china EDF production has given the word "composite" a very bad reputation ...

Nowadays most of the china stuff looks very good (great for internet sales ) but is cheap heavy polyester and grossly overweight ... prices are very low though, and they come prepainted ! Occasionally there's one that is pretty good but many aren't great fliers ...

Did you notice how much of that china shiny polyester stuff is bought and NEVER flies ?

Nevertheless if you are aware of the weight issue and build them really LIGHT you can get a decent flying edf out of them (eg CMP T-45).

.
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Old Sep 13, 2012, 02:11 AM
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Hi Graham,

I think it is more a "large lightweight foam" vs. "small heavy composite" issue ... As far as I know many smallish composite china-made edf jets suffer from the same problem (CMP, JT, proedf etc.)

In the old days some edf composites were very light, and a work of art in fiberglass-airex-sandwich construction (eg Aeronaut Panther, Aeronaut Rafale, JePe F-16, WeMoTec MiG-15, JetArrows Vampire, RD El Bandito, Scheubeler Hawk, K&A etc.).

Recently some of that china EDF production has given the word "composite" a very bad reputation ...

Nowadays most of the china stuff looks very good (great for internet sales ) but is cheap heavy polyester and grossly overweight ... prices are very low though, and they come prepainted ! Occasionally there's one that is pretty good but many aren't great fliers ...

Did you notice how much of that china shiny polyester stuff is bought and NEVER flies ?

Nevertheless if you are aware of the weight issue and build them really LIGHT you can get a decent flying edf out of them (eg CMP T-45).

.
You are right about them not flying that great. I have been following the HK Hawk thread and there are a few guys that do not even want to fly them once they are built.

The focus however does seem to be towards the composite side moving away from foamies for a lot of the manufacturers.

I only have big foamies of which 2 are glassed, and must say that they actually fly very easily. I would in fact say that some of them even fly easier than some trainers. I have also flown a 120mm Rafael which was a different story all together. I think that the jump from one of the easy flying jets to a high wing loaded jet is pretty big. - Keep the speed up!!!!

The composites do however look very good.
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Old Sep 13, 2012, 11:31 PM
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upstate ny
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REALLY TESTING THE LANDING GEAR:

We were supost to fly my Fly Fly 90mm Hawk at the Neat Fair
this weekend - demoing a new fan system .
I wanted to make a flight video but the first try they were
about to work on the field so it was about to close for 3 days
so I rushed and landed short - and hard but no damage

3 s flight (4 min 27 sec)


I then try a second time , well I must have banged the elevator
while I was transporting the model to the field - as soon as it
tookoff I knew something was wrong - I tryed to land but it hit hard
again this time toreoff 2 retract units .

fly fly 90 mm with elevator servo problems (1 min 6 sec)


the elevators were built so strong ,I guess the blow damaged the
hitec servo - just a few teeth but you saw the results .

hope to have it repaired to fly this weekend
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Old Sep 14, 2012, 02:15 AM
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Quote:
Originally Posted by pulsery2k1 View Post
REALLY TESTING THE LANDING GEAR:

We were supost to fly my Fly Fly 90mm Hawk at the Neat Fair
this weekend - demoing a new fan system .
I wanted to make a flight video but the first try they were
about to work on the field so it was about to close for 3 days
so I rushed and landed short - and hard but no damage

http://www.youtube.com/watch?v=0Shzurr-N8c

I then try a second time , well I must have banged the elevator
while I was transporting the model to the field - as soon as it
tookoff I knew something was wrong - I tryed to land but it hit hard
again this time toreoff 2 retract units .

http://www.youtube.com/watch?v=wVu9j...ature=youtu.be

the elevators were built so strong ,I guess the blow damaged the
hitec servo - just a few teeth but you saw the results .

hope to have it repaired to fly this weekend
I saw the clip on the power consumption of the tested system - looks very interesting....
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Old Sep 14, 2012, 08:22 AM
6 months to finish a rtf
pulsery2k1's Avatar
upstate ny
Joined Jun 2003
1,861 Posts
Graham d

yes something new, this is herb's tread but perhaps this video is a
little better .

f-16VSSPORTJET.wmv (9 min 37 sec)
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Old Sep 14, 2012, 02:06 PM
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Hi Pulser, nice video ... yes those full-flying elevators are definitely delicate in transport as well.

You have a nice flying field there !
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Old Sep 15, 2012, 02:59 AM
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Originally Posted by pulsery2k1 View Post
Graham d

yes something new, this is herb's tread but perhaps this video is a
little better .

http://www.youtube.com/watch?v=N7ALYdm6NH8
Where do these fans come from -more details?
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Old Sep 15, 2012, 07:50 PM
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upstate ny
Joined Jun 2003
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Graham d

this herb's tread - sent you a Pm

Thanks Herb

but the site is in a state Park , and its is a lot smaller than it looks
a lot of restrictions - size of models - speed , motor type
great for 70 mm edf's and heli's , my 90mm hawk is at the
large limit .
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Old Sep 16, 2012, 02:37 PM
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Thanks Pulser, is this a 90mm fan for the Hawk? Details?
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Old Sep 17, 2012, 09:14 AM
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upstate ny
Joined Jun 2003
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Hi Herb

the fan used is a Inline Centrifugal 90 mm Duct Fan , the inlet is
smaller but the fan section is 90 mm .

its much more efficent and allows for more scale intake inlets

con's the plastic model which is in the hawk at the moment
is restricted to only 3 s - sounds lousy . 40 - 50 mph speed range
we have an Aluminum version which is much better and can
handle up tp 6 s nice sound great speed- con cost of building it , very high
( unless - it sent to Asia) .

we will have a see throught model that will be ready soon and I will post
a more complete info on my blog shortly .

I have been told , that there is also a 127 mm one being tested
in Germany , but havn't seen any details
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Old Sep 17, 2012, 10:36 AM
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Quote:
Originally Posted by pulsery2k1 View Post
Hi Herb

the fan used is a Inline Centrifugal 90 mm Duct Fan , the inlet is
smaller but the fan section is 90 mm .

its much more efficent and allows for more scale intake inlets

con's the plastic model which is in the hawk at the moment
is restricted to only 3 s - sounds lousy . 40 - 50 mph speed range
we have an Aluminum version which is much better and can
handle up tp 6 s nice sound great speed- con cost of building it , very high
( unless - it sent to Asia) .

we will have a see throught model that will be ready soon and I will post
a more complete info on my blog shortly .

I have been told , that there is also a 127 mm one being tested
in Germany , but havn't seen any details
Pulsery,

Good luck with sorting out the fan - I will be watching closely
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Old Sep 17, 2012, 01:43 PM
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Irvine, Calif USA
Joined Feb 1999
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The 90mm foam jet segment has become very popular...

This is the new Fiat G-91 Frecce Tricolori in foam shown at JetPower 2012 in Germany:

http://www.rc-network.de/forum/showt...ebArt-Fiat-G91

.
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Old Sep 17, 2012, 01:55 PM
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United States, TX, Grand Prairie
Joined Nov 2005
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Quote:
Originally Posted by pulsery2k1 View Post
Hi Herb

the fan used is a Inline Centrifugal 90 mm Duct Fan , the inlet is
smaller but the fan section is 90 mm .

its much more efficent and allows for more scale intake inlets

con's the plastic model which is in the hawk at the moment
is restricted to only 3 s - sounds lousy . 40 - 50 mph speed range
we have an Aluminum version which is much better and can
handle up tp 6 s nice sound great speed- con cost of building it , very high
( unless - it sent to Asia) .

we will have a see throught model that will be ready soon and I will post
a more complete info on my blog shortly .

I have been told , that there is also a 127 mm one being tested
in Germany , but havn't seen any details
What's making the cost high for US production?

We talking about > 100usd?

Can it handle high power?

NASA know about it ?

Thx in advance for any input
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Old Sep 29, 2012, 03:25 PM
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Irvine, Calif USA
Joined Feb 1999
12,177 Posts
I decided to take a picture of the two FlyFly fast foam cousins next to each other ...

The F-86 Sabre has been down for a fan upgrade ... The mechanics are really taking their time on this one.

.
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