Logo
Builders' Plan Gallery  |  Hip Pocket Web Site  |  Contact Forum Admin  |  Contact Global Moderator
September 22, 2018, 09:14:59 PM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with email, password and session length
 
Home Help Search Login Register
Pages: 1 2 3 [4]   Go Down
Print
Author Topic: 6" Indoor Gliders  (Read 7672 times)
0 Members and 1 Guest are viewing this topic.
ptlove
Silver Member
****

Kudos: 11
Offline Offline

United States United States

Posts: 179

WWW

Ignore
« Reply #75 on: August 04, 2009, 02:18:42 PM »

Bill and John, you should have the spreadsheet by now in your email boxes.

Bill, regarding the video there's more detail on this video and how I calculated launch speed with it on this thread, reply #15. The frame rate was 30 FPS.  http://www.hippocketaeronautics.com/hpa_forum/index.php/topic,1722.msg13130.html#msg13130
Logged
ricardo
Silver Member
****

Kudos: 9
Offline Offline

Australia Australia

Posts: 189



Ignore
« Reply #76 on: August 11, 2009, 06:40:07 PM »

I then stumbled accross a CLG trimming document on SFA and read a few of the points in regard to incidence and elevator being lower than the wing by "x" amount.
Lem, which SFA document was this?
Logged

An engineer is someone who can do for 2 bob what any fool can do for a quid
PiperCub49
Silver Member
****

Kudos: 3
Offline Offline

United States United States

Posts: 201


Cub Crazy!!!



Ignore
« Reply #77 on: August 11, 2009, 06:46:42 PM »

http://www.smallflyingarts.com/Downloads/Downloads.htm

HTH,
PC49
Logged
lemuel
Platinum Member
******

Kudos: 59
Offline Offline

Australia Australia

Posts: 1,813


A peanut a day keeps the doctor at bay..

WWW

Ignore
« Reply #78 on: August 11, 2009, 08:59:54 PM »

like pipercub said.. it is in the top header of the first webpage under the glider banner.. it is a great document.

regards
Matthew
Logged

two wings = GOOD, no wings = BAD Sad
ricardo
Silver Member
****

Kudos: 9
Offline Offline

Australia Australia

Posts: 189



Ignore
« Reply #79 on: August 11, 2009, 09:48:26 PM »

like pipercub said.. it is in the top header of the first webpage under the glider banner
Do you mean John Koptonak's "10 Step Flight Trimming Guide"
Logged

An engineer is someone who can do for 2 bob what any fool can do for a quid
PiperCub49
Silver Member
****

Kudos: 3
Offline Offline

United States United States

Posts: 201


Cub Crazy!!!



Ignore
« Reply #80 on: August 11, 2009, 09:57:13 PM »

I decided that I would finally build the 6" DogChew. I'll be done here in a couple of minutes. Let's see if I can get it under 5g. Cheesy Where should I put my throw tab?

-PC49
Logged
lemuel
Platinum Member
******

Kudos: 59
Offline Offline

Australia Australia

Posts: 1,813


A peanut a day keeps the doctor at bay..

WWW

Ignore
« Reply #81 on: August 12, 2009, 02:44:06 AM »

There are several documents. Just go to the Glider part of SFA and above all the other posts are 2 important posts. One is called Caley asked for: Glider Pros[?]Secrets & Tips in that thread are a few documents. Has been a fantastic help to me.

regards
Matthew
Logged

two wings = GOOD, no wings = BAD Sad
PiperCub49
Silver Member
****

Kudos: 3
Offline Offline

United States United States

Posts: 201


Cub Crazy!!!



Ignore
« Reply #82 on: August 12, 2009, 05:13:16 PM »

Matthew,

What kind of flight times are you getting on your DogChews?

-PC49
Logged
lemuel
Platinum Member
******

Kudos: 59
Offline Offline

Australia Australia

Posts: 1,813


A peanut a day keeps the doctor at bay..

WWW

Ignore
« Reply #83 on: August 12, 2009, 06:07:23 PM »

My most consistant flight times have been indoors. I was regularly getting 25+ seconds in a 13meter high ceiliing. Out doors I have had them fly away. They have flown 30 seconds plus outdoors from handlaunch. I usually fly them in low lift conditions (late afternoon) also. Please make one and let me know how your go. I takes 1hr to make one.

regards
Matthew
Logged

two wings = GOOD, no wings = BAD Sad
PiperCub49
Silver Member
****

Kudos: 3
Offline Offline

United States United States

Posts: 201


Cub Crazy!!!



Ignore
« Reply #84 on: August 12, 2009, 06:34:29 PM »

I guess I have three words: I need help! I have already built one (finished it last night). I new that my DogChew would be no winner, coming in at 2.3g (BRICK!). I build it with lighter wood than the plans called for. My wing was hard 1/32" and my fuse was contest grade 1/8". I sanded my tail surfaces to about 1/64". Glue was of course used very sparingly. My longest flight time was about 18 seconds. I never did get to trim it like it should have been before she met her death. I though that you posted some pictures of your DogChews on SFA. Am I right?

I am going to try my hand at the 8" Sweepette.

Thanks,
PC49
Logged
lemuel
Platinum Member
******

Kudos: 59
Offline Offline

Australia Australia

Posts: 1,813


A peanut a day keeps the doctor at bay..

WWW

Ignore
« Reply #85 on: August 12, 2009, 10:37:38 PM »

I never use hard for my wings. I always use the lightest stuff that I am willing to part with. These little gliders "always" break. They are regarded as being dispensible too. My advice would be to get the lightest sheet of 1/16th you have and don't make the fuse out of 1/8 make it out of 1/16th. Mine is not a skyrocket but it does float and needs next to no wind to fly nicely.

The Dog chews I made were deleted from SFA for some reason, I think the server went down or something.

regards
Matthew
Logged

two wings = GOOD, no wings = BAD Sad
PiperCub49
Silver Member
****

Kudos: 3
Offline Offline

United States United States

Posts: 201


Cub Crazy!!!



Ignore
« Reply #86 on: August 12, 2009, 11:17:01 PM »

Few, they disappeared and I thought that I was going crazy! Thanks for the advice. I will be making more DogChews...well, right after I finish my 13" DH-6.Smiley

-PC49
Logged
lemuel
Platinum Member
******

Kudos: 59
Offline Offline

Australia Australia

Posts: 1,813


A peanut a day keeps the doctor at bay..

WWW

Ignore
« Reply #87 on: August 12, 2009, 11:38:55 PM »

that happens sometimes, the server goes down and attachments get deleted. The sweepette 8" is another design that flies really well. I think Joshua Finn designed this version. if I can offer advice it is to make one of these. I let my son have some shots with it on the rubber catapult. One of his shots clipped his arm and tore the rudder and elevator off. So I had to make the fuse shorter. I made sure that I made the decelage as close to 0-0 as possible and it goes straight up like an arrow Grin It then does the "bunt" and flies away nicely. It did this repeatedly for 15 minutes and then after that it would not do it any more?? strange things these little gliders.

I think that the way the glider settles into the glide is important. I like to get my gliders facing into the wind when they start to glide. I also like to have the model launching with the wind going over my shoulder so that the model under power slowly turns right and then settles into the left hand glide path.

regards
Matthew
Logged

two wings = GOOD, no wings = BAD Sad
Maxout
Titanium Member
*******

Kudos: 87
Offline Offline

United States United States

Posts: 2,642


WWW

Ignore
« Reply #88 on: August 13, 2009, 07:58:15 AM »

Since I did come up with the Sweepette 8, here are some comments:

For indoor flying, light 1/16 would be ok. For outdoor, you need somewhat hard stuff, 10 lb 1/16" C-grain is your best bet (do not skimp on this or you will be picking up small pieces after the first real launch). Find the hardest piece of 1/8" balsa you can for the fuselage. Tail surfaces should be 1/32" C-grain sanded to a knife edge. The wing should be sanded to a conventional HLG airfoil. LE should be razor sharp, TE should be 1/64" thick. Taper the thickness toward the tips. Give the entire model several coats of minwax to thoroughly seal it. Make absolutely sure that there is NO washin in the right wing. Left wing needs at least 1/16" wash in the inboard panel. Both tips are washout out 1/16". You need a tiny bit of left rudder (start with less than 1/64" and add more until it rolls left at the end of the climb) DO NOT, I repeat, DO NOT try to use 0-0 incidence. You will fail miserably. Set the incidence exactly as per the plans and bend in tiny bits of down elevator until it tracks straight for the first part of the climb, then rolls off to the left.

I'd recommend against being around spectators for first flights with these. I pull the catapult all the way back, so they come off as missiles and are pretty dangerous if anything goes wrong.
Logged
Alexandre Cruz
Bronze Member
***

Kudos: 11
Offline Offline

Brazil Brazil

Posts: 66



Ignore
« Reply #89 on: October 26, 2009, 01:15:49 PM »

This is the most reasonable explanation of natural bunting in tiny gliders I could figure out:

Bunt ability is very related to CG, elevators chord and flexibility in small gliders.

When launching, Reynolds number will increase by many times the gliding Reynolds (trimmed condition). If you consider a rigid model (I fly mostly outdoors) and your model trims at a positive CL (same as wing lift direction, decalage...) in the elevator it will bunt.

Most of this comes from the fact of when Reynolds number is increased, a variation at wing and elevator CL occurs. As elevator’s Reynolds number is very small, its Reynolds variation produces a significant variation in CL. In the wing however, this variation is not so high due to initial “high” Reynolds number so, the model is untrimmed (almost 10% in trim moments difference) and will pitch down during climb. In case your model does not bunt increase elevators aspect ratio.

Flexibility is also important, in this case, positive CL for trim, elevator flexibility will tend to reduce the bunt ability but wing’s flexibility will increase that. As most outdoor elevators are more rigid than the wing and the aerodynamic argument applies, the model tends to bunt.

What do you guys think?
Logged
Olbill
Titanium Member
*******

Kudos: 55
Offline Offline

United States United States

Posts: 2,354

Topic starter


Ignore
« Reply #90 on: May 28, 2014, 10:00:52 AM »

The Beast flies again!!!

I gave my 3 yr old grandson an old HLG to fly but it was too large for him to throw. I had my original beast on a shelf so figured that would be a better plan. A quick new stab and a long piece of very thin rubber (to limit the amount of potential damage or injury and it was back flying again. The first hurdle was getting James to pick it up by the fuse. That took a couple of repairs but finally sunk in. Then the launch angle was tackled. Out of maybe 8 or 9 tries he got two spectacular flights. At that point the wind was coming up a little so we quit for the day.
Attached files Thumbnail(s):
Re: 6" Indoor Gliders
Logged
boca55
Silver Member
****

Kudos: 6
Offline Offline

Serbia and Montenegro Serbia and Montenegro

Posts: 117




Ignore
« Reply #91 on: May 30, 2014, 02:59:13 AM »

I Serbia and Croatia we have category F1N-150 (catapult indoor gliders wingspan 150mm). I n region we have about 9-10 competitions in category F1N and F1N-150.
Here is some plans F1N-150
Attached files Thumbnail(s):
Re: 6" Indoor Gliders
Re: 6" Indoor Gliders
Re: 6" Indoor Gliders
Logged
Olbill
Titanium Member
*******

Kudos: 55
Offline Offline

United States United States

Posts: 2,354

Topic starter


Ignore
« Reply #92 on: May 30, 2014, 03:53:29 PM »

Thanks for the plans! I may try to get some of my club members to try this class. It looks like fun.
Logged
xptical
Copper Member
**

Kudos: 0
Offline Offline

United States United States

Posts: 5



Ignore
« Reply #93 on: March 26, 2018, 02:35:12 PM »

I built The Beast and Vampir over the weekend.  They are both wonderful fliers.

How are you getting 0.5gm on The Beast?  My wings started as 1/16", but are now paper thin.  They are at 0.4gm each!  Just for the wings.

Vampir out of balsa is maybe 5 grams (after repairs) and the Beast is like 2 grams.

I'm currently using 3/32" hard balsa stick for the fuse.  I could probably go thinner.  I'm considering using 2 layers of thinly-sanded 1/32 with a layer of carbon thread down the center.


As this thread is fairly old, are these (short wingspan/thick chord gliders) still considered competitive?
Logged
Olbill
Titanium Member
*******

Kudos: 55
Offline Offline

United States United States

Posts: 2,354

Topic starter


Ignore
« Reply #94 on: March 26, 2018, 05:42:21 PM »

There is a Facebook group called "Everything about F1N". You can find a lot of very recent info on the F1N-150 gliders. I haven't thought about the Beast for several years so anything that isn't in this thread is probably lost.

The F1N-150's are posting times in the low to mid thirties in the competitions that I'm aware of. I've seen a number of them in the .5g weight range.

Logged
Pages: 1 2 3 [4]   Go Up
Print
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!