Notices
RC Gliders, Sailplanes and Slope Soaring Discuss rc gliders,rc sailplanes and slope soaring in this forum. Thermaling techniques, airfoils, tips, etc

Hobie Hawk set up

Old 05-19-2005, 10:17 AM
  #1  
kamakasi
Senior Member
Thread Starter
My Feedback: (3)
 
kamakasi's Avatar
 
Join Date: Sep 2003
Location: butternut, WI
Posts: 405
Likes: 0
Received 0 Likes on 0 Posts
Default Hobie Hawk set up

Damn my wife loves me. Last night she informed me that for our anniversary she got me a vintage Hobie Hawk. So in a flurry of Internet activity I tried to find out all I could about the set up and flight characteristics of the Hawk. I found HobieHawk.com and they had tons of useful information. Are there any quirks that one should know about before flying. As I understand it the Hawk if set up properly is a fantastic plane. If set up a little sloppy it can be a real PITA.
Considering this plane is from the late 70's early 80's I am going to replace the push rods. I've read that they can fail with this much age behind them. All suggestions and tips are welcome.
Old 05-19-2005, 12:40 PM
  #2  
elfwreck
Member
 
Join Date: May 2005
Location: , CA
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

Hey now,
The hobie is a great plane as long as you're aware of certain um characteristics. Because of the parabolic dihedral they will "dutch roll" like crazy.
This can be a lot of fun on the slope, but can make landings scarey as... well very scarey.
In flight they really look like the nose is pointed way down, check the angle of the wing on the fuse and you should see what I mean.
Also this is one of the few rudder elevator planes that doesn't need full kick on the rudder.
The up side; it'll do great barrel rolls as well as snap rolls, spins (easy to get out of), and if you're really on it, fly inverted. Just be very, very carefull on landings or it'll ground loop, it's that dutch roll thing again.
Enjoy your new toy, I dearly love mine even if I don't fly it that often...
RobII
Old 05-22-2005, 08:34 PM
  #3  
kingbee
Member
 
Join Date: Nov 2002
Location: Ironwood, MI
Posts: 89
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

Hey Joe, lucky you!

I've owned two Hawks over the years, and sold the last one about 5 years ago.

Here's some tips:
Washout is essential, about 1/4" or so.
Setting the CG is critical, and it's not a simple as balancing it on your fingertips. Do you have the manual? It shows how to do it, a rather bizarre procedure compared to what you may be used to.
Don't let the attitude of the fuselage fool you into flying it too slowly. The stall is vicious. Keep the nose down!
When landing, don't try to grease it in or that low nose will pop you right back up into the air. Try to smoothly flare it in, but not too high, the stall is vicious.
Don't try any tight, Sailaire style turns, at least not near the ground. The stall is vicious.
When launching, don't just let go of it, THROW it hard and up so that it has flying speed when it leaves your hand. I can't over stress how important this is!

The Hawk is a great plane, and it's capable of amazing performance. However it can be a ***** to fly well. Keep the speed up, be smooth on the controls, and don't worry about spot landings at first.

I've often regretted selling mine. I really need to get over to Park Falls now!

Cheers,
Dave
Old 05-23-2005, 12:29 PM
  #4  
kamakasi
Senior Member
Thread Starter
My Feedback: (3)
 
kamakasi's Avatar
 
Join Date: Sep 2003
Location: butternut, WI
Posts: 405
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

What do you mean "tight sailaire type turns" LOL With the pig you slap in full rudder and then wait to see if the plane condescends to your input. Do I read you right that the Hobie Hawk has a vicious stall. I was already thinking about that nose down flight attitude. I will remember to keep the speed up and the nose down. I have a pair of pop up spoilers do you think I could get them in the wing without structurally impairing it?
Old 10-20-2005, 12:03 PM
  #5  
Spiderman_48
Junior Member
 
Spiderman_48's Avatar
 
Join Date: Jun 2004
Location: Vienna, WV
Posts: 16
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

I have one... --haven't flown it for probably 20-25 years! But I do remember the fuselage attitude problem... on first flights I'd try to keep that nose pitched up and it would prematurely stop flying about 3 feet off the ground[X(].
Nice thing about the model, tho, it's TOUGH! Where I live there is little hope for slope lift, and I was never good at thermal sniffing, so, I opted for a high-start; a fairly strong one, at that. Soooo, I did a whooops[sm=confused.gif] on a high-start launch once, and she did a large arc (~30') and came straight into terra-firma[sm=spinnyeyes.gif]. Sunk the nose into the earth about 4" and did break off a wing tip (epoxied it right back on with some internal hardwood dowels). Wow, that fuse will take some abuse!
Later on, to get a little more duration, I fashioned a power pod with a TeeDee .049 and about a one ounce fuel tank and was able to really tax that air frame. Loops, Spins, Barrel rolls, etc.[sm=lol.gif] It never whimpered.
It may be time to get 'er back out.
Old 10-21-2005, 11:54 AM
  #6  
Liberator
Senior Member
 
Join Date: Mar 2005
Location: Sandy, UT
Posts: 805
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

But how would you describe the stall?


Old 10-21-2005, 12:18 PM
  #7  
Spiderman_48
Junior Member
 
Spiderman_48's Avatar
 
Join Date: Jun 2004
Location: Vienna, WV
Posts: 16
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

[sm=bananahead.gif]THUNK!.....Flubba-Flubba-Flubba-Flubba- ...(that would be the wings flapping). It would drop like a rock!
Old 10-24-2005, 06:47 PM
  #8  
vintagesailplnr
My Feedback: (40)
 
Join Date: Jul 2002
Location: Nesquehoning, PA
Posts: 46
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

Hey Guys:
I'd like to jump in on this Hobie discussion - I have two of the very first Hobies produced - they had the fuzz still attached to routed wing bays - Hobie A. corrected on the next batch of 25.

I have a set of 10 ft wings and I made a larger set of stabs - grey foam and 1/64 ply and a larger rudder. These make the 10 footers really fun to fly. I have been looking for an extra fuse - got one!!! Got it to perfect flying shape - went to insert wing rod --------------woooooow - too small for standard rod, ca 3/64".

Has any one else had this happen? Suggestions?????
1) ream out the fuse slot and insert proper sized brass wing rod tube? Reaming might be not a good idea!!! weaken the area???
2) use smaller wing rod and bush the wing rod tubes in wings?????
3) toss fuse? - BTW, where/what was this fuse made? I think I remember two or three people bought the rights and offered "Hobies" someone changed the dimensions? I've never heard of this modification in past.
TIA
Jim
Old 10-30-2005, 08:51 AM
  #9  
aireze
Junior Member
 
Join Date: Apr 2005
Location: Ocala, FL
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

To somewhat tame the Dutch Roll thing, add a small extention to the front of the fin. Start about 5" in front of the fin and extend it back to a point about 3" high on the fin. This is not an exact science. This mod and a little washout will help tame the beast. Good Luck
Old 11-12-2005, 11:57 AM
  #10  
Toomanyplanes
Member
 
Toomanyplanes's Avatar
 
Join Date: Feb 2005
Location: Anacortes, WA
Posts: 76
Likes: 0
Received 1 Like on 1 Post
Default RE: Hobie Hawk set up

Sounds like you got a very early prototype. Small sleeve in the fuselage? Hmmm... I think I would put that fuselage on the shelf and find a different one with the right size sleeve. Don't use a smaller wingrod. Not strong enough and it might seize in the sleeve or wing. Without knowing what sleeve is in the fuselage I would be averse to reaming it out unless there was enough "meat" on the insert to do this operation. Use of a hand reamer might work if you decide to do it anyway. Digging the insert out is suicide as they were molded into the polyethelyne and it would take a small nuclear device to get it out. The sleeve is a hefty custom made aluminum extrusion that has about 15 splines on it's exterior to help it grip onto the poly material. That's the way it is on the production versions anyway...

The fuzz on the wing bays is on the freshly routed wings and Hobie sent gobs of the wing panels out to have them sanded before shipping. Very time consuming and tedious work. I have to sand every bay, top and bottom, on the Superhawk before shipping.

The washout in the wing is absolutely necessary. The story of the Hawk that wiffer-dilled on launch and pummeled into the ground was (is) common. The culprit was usually the wing washout or asymmetrical washout due to repairs or just not being checked before flying for the season. Monokote and other synthetic films do relax over time and with temperature variations so check the washout often. The wing on the hawk is extremely rigid and will untwist itself over time. NEVER store any of your planes with loads on them as it will twist the airframe. The 1/4" washout is bare minimum. I use more like 7/16" and check that both wings are the same. If you are going to thermal this plane you MUST have the tip stall issue resolved first. Spiral turns are next to impossible otherwise.

The Hawk is a RES airplane and consequently used alot of "infinihedral" for turning requirements characteristic of all planes utilizing rudder only. This gave it alot of exposure at the wingtips to the relative wind when it was yawed with the rudder or was flying slow and in turbulence and also led to the characteristic "Hobie Rock" or Dutch rolling tendency. You cant get rid of it totally as it is related to the wing design but it can be minimized. Extra area added to the fin was common many years ago but the fact is that the tailboom was too short and the rudder was too small on the original design. Using Ten foot wings without a longer tailboom/larger rudder on this plane is just "plain" scary. It is bad enough with the 8 footers.

I guess you could compare it to a Pitts Special. If you only fly stable aircraft like a Cessna 172 you can't expect to jump into the Pitts without knowing how it flys first.

I fly my Hawks both thermal and slope, off winches (carefully) and heavy duty high starts. The simple two channel set up is a bit retro but there's nothing like flying a hawk on a warm afternoon in a sea breeze. Brings back memories... But, I digress.

Visit www.Hobiehawk.com for lots more info.

Tony





Old 11-12-2005, 07:08 PM
  #11  
kamakasi
Senior Member
Thread Starter
My Feedback: (3)
 
kamakasi's Avatar
 
Join Date: Sep 2003
Location: butternut, WI
Posts: 405
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Hobie Hawk set up

O.K. just an update on the hawk. Alas it has cede to be.( This parrot is no more) I was out flying the other day and had a slightly rough landing nothing major but not as pretty as usual. Well I checked out the plane and everything seemed fine ( except the crack in the rudder control horn) on the next launch the hawk went up then to the right the I said oh *****!!! and it impacted the ground at a great rate of speed. All that is reusable is the fuselage the wings are in many pieces along with the stabs and rudder. At least I am thorough. Time to shop for a "new" hawk.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2022 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.