Sky Master Hawk
 

Would like to know comments on SM Hawk, landing and flight ?
Thanks in advance.

RE: Sky Master Hawk
 

very stable aircraft all round seen a few fly and nothing but praise from the pilots

RE: Sky Master Hawk
 

do a search, there are MNAY topics on the Skymaster hawk. the topics will give you the pro's and con's. There is another topic going now about the fuel system. NIce jet and easy to build.

Mark

RE: Sky Master Hawk
 

Like Mark said, there are plenty of Skymaster Hawk posts in this forum, which you should be able to find with a search. IIRC, David Gladwin also reviewed it in the RCJI mag, so you may want to hunt down a copy of the article. From what I've read, it seems to be a well thought of aircraft, though if I remember correctly there is a potential "gotcha" with pitch control with the flaps down at certain speeds (?) - I don't recall the exact details, but a search should turn it up, or someone will post the info here. I believe it was something about possibly running out of elevator control if you don't use the flaps in exactly the way that is prescribed by the manufacturer. (i.e. it should be fine as long as you pay attention to that particular part of the instructions). If in doubt, contact Ali Machinichy (sp?) to get his input, as I'm fairly sure he's one of the guys who posted here about the correct way to use the flaps on this aircraft. Note that I don't in any way mean the preceding as something to scare you away from the aircraft - just a heads-up to ensure that you have fun with your Hawk if you do buy it.

RE: Sky Master Hawk
 

I gutted one and re-stuffed it a couple of months ago. I suggest a matchbox and two 8611's on the horizontal stab.

I maidened said aircraft for it's owner about a month ago. The airplane was rock steady at any speed.

With full flaps I came in for an approach and everything was great. I overshot the runway and went carefully to full power. Just on climbout in a shallow left bank I "felt" the elevator go soft. I had been expecting to see something related to the elevator with flaps down.

I immediately came back off the power a little bit and raised the nose even more and elevator came right back solid.

So now I know ;)

FWIW.

By the way, the landing by all accounts was the best one I've had in quite a while. It was a beautiful flight !!

RE: Sky Master Hawk
 

I think you said that just to restart the eternal argument about where to use matchboxes & where not to !

RE: Sky Master Hawk
 

I'm not afraid to put them anywhere. If something is going to fail, it's just going to fail.

But on this application, you have two 250 ounce servos with each their own push rod, angled at one control horn.

When I receeived the airplane and put my amp meter on it, the reading was 3.5 amps at idle.

I shut everything down and started investigating.

No matter how you measure the rods etc. You can't line up two digital servos that accurately.

Well, maybe you can, but I can't.

Matchbox saved it for us.

Works great!

I've had four jets with a matchbox on a primary flight surface, but you know me, I fly JR, I'm such an 'outlaw' :D:D:D

RE: Sky Master Hawk
 

Just for the record:
This is a common problem in larger 30% prop models when twin servos are used for rudded control.
If Hitec digital programmable servos are being used it is possible to adjust end points (travel), center position and ALSO the individual dead band of each servo to eliminate the two servos to fight each other.
For sure it seams like a very good idea to check the current draw of each servo.
/Johan