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aeppel_cpm
07-14-2013, 09:12 PM
So is the best glide of a boosted glider's life usually it's last?

Our little family launches had two notable flights today - our entry into mid-power - Big Daddy on a D12-3, and the best and last flight of our Centuri Hummingbird clone.

This was the scratch build that brought me back into rocketry - the model I loved best as a youth. Last year I cloned it, and a BT50 version. We fly out of an orchard just to the north of Bong, in SE WI. I figure we can fish a rocket out of any tree in the orchard - we've got the ladders handy.

On an A8-3 it lifted high, looped over as normal and then settled into a lovely slope with the wind. And didn't turn again. We last saw it sailing over a fencerow of hickory, still >50' up, and on into the soybean field to the west. Presumably.

I have a feeling of vu ja day. This is going to happen again. Is this the sad fate of the best gliders?

Charles

shrox
07-14-2013, 09:23 PM
So is the best glide of a boosted glider's life usually it's last?

Our little family launches had two notable flights today - our entry into mid-power - Big Daddy on a D12-3, and the best and last flight of our Centuri Hummingbird clone.

This was the scratch build that brought me back into rocketry - the model I loved best as a youth. Last year I cloned it, and a BT50 version. We fly out of an orchard just to the north of Bong, in SE WI. I figure we can fish a rocket out of any tree in the orchard - we've got the ladders handy.

On an A8-3 it lifted high, looped over as normal and then settled into a lovely slope with the wind. And didn't turn again. We last saw it sailing over a fencerow of hickory, still >50' up, and on into the soybean field to the west. Presumably.

I have a feeling of vu ja day. This is going to happen again. Is this the sad fate of the best gliders?

Charles

Yes.

Treat them as laboratory animals and do not get attached to them.

A Fish Named Wallyum
07-14-2013, 09:54 PM
So is the best glide of a boosted glider's life usually it's last?

Our little family launches had two notable flights today - our entry into mid-power - Big Daddy on a D12-3, and the best and last flight of our Centuri Hummingbird clone.

This was the scratch build that brought me back into rocketry - the model I loved best as a youth. Last year I cloned it, and a BT50 version. We fly out of an orchard just to the north of Bong, in SE WI. I figure we can fish a rocket out of any tree in the orchard - we've got the ladders handy.

On an A8-3 it lifted high, looped over as normal and then settled into a lovely slope with the wind. And didn't turn again. We last saw it sailing over a fencerow of hickory, still >50' up, and on into the soybean field to the west. Presumably.

I have a feeling of vu ja day. This is going to happen again. Is this the sad fate of the best gliders?

Charles
Add an extra bit of clay or a heavy fillet to the far edge of one of the fins. Maybe it will induce more of a turn to that side and have more of a corkscrew return path.

atticus
07-14-2013, 11:36 PM
Back in July 2007, I flew my Squirrel Works Mega Red Baron on it's first flight.
The club - Vikings Rocket Society NAR 203 - was flying from a field at the far end of local county park.
This thing is large and heavy, so trimming tests in the yard couldn't tell me much. But, the CG was dead on per the instructions, so I figured I'd take the chance.
Boost on a D12-3 went fine the motor ejected and it settled into a beautiful glide.
Straight and a better glide rate than I expected. On and on it went towards the more used end of the park. It was getting farther and farther away, then, when about 4 feet off the ground I was feeling proud and wondering how the landing would be when it just STOPPED DEAD IN THE AIR. Dropped to the ground!
It had hit the cross pipe at the top of the outfield fence of a recently built LL baseball field.

This wasn't its last flight, but is was its best.
I repaired the carnage but must have overlooked something. On the next months try something gave loose and it broke apart in a couple of places on boost.
I repaired it well and repainted. It was hung from the end of one of the pipes suspended from the ceiling that holds some of the longer rockets.
And there it stayed until.....
Two years ago, I was sitting here at the computer, when the earthquake hit - epicenter about 10 miles down the road. At first I didn't think anything of it, but it kept getting stronger and I stood( to do what ,I wasn't sure) and noticed the Red Baron swaying on the pipe. I head for it, it worked its way off and I managed to catch it before it hit the concrete floor.
One day it will fly again.
Tim

fulldec
07-14-2013, 11:45 PM
So is the best glide of a boosted glider's life usually it's last?



Usually not if you have radio control! :)

Mark II
07-15-2013, 01:01 AM
I have never faced any risk of having any of my gliders fly out of sight.

The best glides that I have ever gotten came down well short of the field's edge, and that was in a small field. My personal best was almost 10 secs. in duration, which was a major triumph and was easily twice as long as my previous personal best. I haven't been able to repeat that performance in any flight since then, but I keep trying. Eight years into it, I keep hoping for some kind of breakthrough. According to everything that I have read, people do actually succeed in getting these things to boost and glide. Even having both things occur during the same flight, from what I hear. It's totally mind boggling to even think about.

Usually my gliders' last flights are the ones in which they break up upon landing.

aeppel_cpm
07-15-2013, 07:43 AM
Bill, thanks for the wingtip weight suggestion. I'll try it with the surviving Hummer-50.

Don - working on it. I had planned to scavenge the parts from my boy's Cox Sky Ranger when he broke it - but he went and lost it entirely instead.

I checked the videos of the flights and we lost sight of the Hummingbird at around 15 seconds - which I figure is pretty good for that design. It doesn't have a reputation for duration.

We also flew an Estes Tercel - which swooped and swirled beautifully for a roughly 27 sec flight. (On a 1/2A4-2T)

ghrocketman
07-15-2013, 09:16 AM
Every one of my boost gliders flies fairly decent, EVEN the orbiters on the Orbital Transport and Scale Estes Space Shuttle. Both of those needed a ton of trimming and a lot less up elevon and more noseweight.

fulldec
07-15-2013, 09:18 AM
There is a wide range of boost gliders. Many kits are what I classify as "novelty" gliders. They look cool, you usually paint them (which makes them heavy) and they barely glide. They can be fun, but they aren't much of a true glider.

Kits like the Estes Tercel and Semroc (used to be a Centuri kit) Swift are more of a performance glider type design. They are a good way to get into performance type small gliders. Once you get them working, you may clone them with better balsa you can hand select.

If you want long durations, don't weigh you glider down with paint. One or two coats of model airplane dope thinned 50% is all you want. For color, you can use fat magic markers. It is not a show quality finish, but it works and weighs nothing.

I have gotten to where I will build 2 or 3 at a time. It doesn't really take a lot more time to build a couple than it does just one. That also gives you a spare in case it flies away.

Once you build them, you definitely need to trim them to fly nice. First you toss them and add weight to get them to glide straight. Start with it balancing about a 1/3 way back from the front edge of the wing (without the boost pod) You usually have to add weight (modeling clay) on the nose to make it stop stalling (it wants to climb, then dive, climb then dive). If it just wants to dive into the ground, add some tail weight, but that should not be the case with one of these models, check all the surface for warps, or things not glued correctly.

Now once it is flying straight, you want to make it turn in a circle or it will turn downwind and fly out of sight when you launch it. Sometimes there is enough asymmetry in the model that it will turn on its own. If so just work with that. If not, it is time to take matters into your own hands. Add a little weight to the wing tip. It will turn toward the heavier side. You will probably have to remove a little nose weight when you add that weight to the wing.

Keep tossing and adjusting until you get it flying the way you want. Then go launch. It helps to have a 4' rod or take your 3' rod and tape it to a 3' dowel stuck in the ground. That allows the glider to have more usable launch rod length to guide it and gives you a much better boost.

Have fun, gliders are the best!

Don

chrism
07-15-2013, 03:59 PM
My first and only flight of a glider was an Edmonds Tinee. I used a 1/4 A 13mm enigine on its maiden flight. Upon ejection of the engine, it was just enought for it to land in a tree. It was a nice little kit and not that expensive I plan to get another.

A Fish Named Wallyum
07-15-2013, 04:33 PM
My first and only flight of a glider was an Edmonds Tinee. I used a 1/4 A 13mm enigine on its maiden flight. Upon ejection of the engine, it was just enought for it to land in a tree. It was a nice little kit and not that expensive I plan to get another.
The CiCi is also great. Mine has gotten stuck in the same tree twice and tumbled out the next day.

Mark II
07-16-2013, 02:40 AM
All of my gliders have been scratch-built from plans, and I have never put a drop of paint or any other kind of coating on any of them. I do carefully trim them so that they make respectable glides of 20-30 feet with hand tosses, but none of that is ever evident following a rocket-propelled boost into the sky. In the one good glide that I have gotten over the years the glider descended at about a 30-35 degree angle relative to the ground. The rest have been anywhere from 45 degree to over 60 degree parabolic flights. They have all been front-engine motor pop types like the Estes Falcon and the AMROCS Wombat. The one good glide was with the Wombat on a 1/2A6 and it had more than a little help from a gust of wind that blew across the field at just the right moment. I also tried several times to construct a flyable Astron Invader, tweaking the angle of the motor in relation to the wing, with zero success. (Every flight arced right into the ground under thrust, with the impact breaking the glider.)

I did build an Edmonds Micro Deltie once for competition, but upon ignition the glider shattered under the thrust of the 1/4A motor.

I don't know what kind of magical touch is required to get anything like these to glide following a boost into the sky; I have never been able to find a way to acquire it even though I have been diligently searching for it for years.

Mark II
07-16-2013, 03:28 AM
There is a wide range of boost gliders. Many kits are what I classify as "novelty" gliders. They look cool, you usually paint them (which makes them heavy) and they barely glide. They can be fun, but they aren't much of a true glider.

Kits like the Estes Tercel and Semroc (used to be a Centuri kit) Swift are more of a performance glider type design. They are a good way to get into performance type small gliders. Once you get them working, you may clone them with better balsa you can hand select.

If you want long durations, don't weigh you glider down with paint. One or two coats of model airplane dope thinned 50% is all you want. For color, you can use fat magic markers. It is not a show quality finish, but it works and weighs nothing.

I have gotten to where I will build 2 or 3 at a time. It doesn't really take a lot more time to build a couple than it does just one. That also gives you a spare in case it flies away.

Once you build them, you definitely need to trim them to fly nice. First you toss them and add weight to get them to glide straight. Start with it balancing about a 1/3 way back from the front edge of the wing (without the boost pod) You usually have to add weight (modeling clay) on the nose to make it stop stalling (it wants to climb, then dive, climb then dive). If it just wants to dive into the ground, add some tail weight, but that should not be the case with one of these models, check all the surface for warps, or things not glued correctly.

Now once it is flying straight, you want to make it turn in a circle or it will turn downwind and fly out of sight when you launch it. Sometimes there is enough asymmetry in the model that it will turn on its own. If so just work with that. If not, it is time to take matters into your own hands. Add a little weight to the wing tip. It will turn toward the heavier side. You will probably have to remove a little nose weight when you add that weight to the wing.

Keep tossing and adjusting until you get it flying the way you want. Then go launch. It helps to have a 4' rod or take your 3' rod and tape it to a 3' dowel stuck in the ground. That allows the glider to have more usable launch rod length to guide it and gives you a much better boost.

Have fun, gliders are the best!

DonThis all sounds so nice that I just about want to cry, because in the reality that I live in none of it ever, ever happens. I have been at this for eight years now.

fulldec
07-16-2013, 08:34 AM
This all sounds so nice that I just about want to cry, because in the reality that I live in none of it ever, ever happens. I have been at this for eight years now.

Man, I can't imagine why you have such poor luck with your gliders. The Falcon and Wombat are not going to give you the best gliding performance, but they ought to do better than that!

Do you know anyone who flies gliders well, or can you take a model to a launch/contest where there are folks flying gliders? Most anyone I know who flies gliders would be more than happy to check out your model and see what's going on.

If you still want to give it a go, try the Tercel or Swift (front engine pop pod kits). For a minimal investment you can build one from the plans on the NAR boost glider page (https://sites.google.com/site/xnarcompetition/duration-events/boost-glide-duration)

There are some complex models there, but the Honeybee, Delta Z, and Flybaby look to be pretty simple. The Manta is a pretty bullet proof glider of modest capability. Many use it to insure a qualified flight and many have won contests with them.

There are articles on trimming and other techniques. Some of the other plans provide lots of detailed instructions for how to sand the airfoil and built the model that would apply to other designs.

You can do this.

Don

blackshire
07-20-2013, 01:26 AM
This all sounds so nice that I just about want to cry, because in the reality that I live in none of it ever, ever happens. I have been at this for eight years now.Oh dear...both you *and* Solomoriah are experiencing this! I can think of one possible way out of this..."negative stasis" (for you, Solomoriah, and others who have difficulties with boost-gliders):

In his "Handbook of Model Rocketry," G. Harry Stine wrote about 'fair-weather models' and 'foul-weather models' where boost-gliders (B/Gs) are concerned. The slower-gliding fair-weather B/Gs are somewhat tricky to trim (and sometimes -very- tricky to trim). They also require calm or nearly-calm wind conditions. The faster-gliding 'foul-weather' B/Gs have higher wing loading (they are heavier and/or have smaller wings) and good wind penetration, and they are less prone to being 'upset' (knocked into a stall or spin during the glide) by changing wind currents aloft. Such B/Gs are usually easier to trim for a good glide, and they also have more stable boosts because of their higher wing loading. Also:

There are several 'foul-weather' boost-gliders that I think would work well for you. The Centuri Mini-Dactyl (see: http://www.semroc.com/Store/scripts/ClassicParts.asp?ID=591 [Semroc has *all* of its parts available!]) can fly with either one or both of its two delta wing/canard gliders, which makes it possible to simultaneously test two trimming techniques in one flight. The Centuri Hummingbird (see: http://plans.rocketshoppe.com/centuri/cenKF-2/cenKF-2.htm , https://sites.google.com/site/centurihummingbird/ , and http://www.semroc.com/Store/scripts/ClassicParts.asp?ID=566 ) is also a good 'foul-weather' B/G--it could also be flown with the streamer-recovered 13 mm motor mount that will come in Semroc's soon-to-be-released Red-Eye kit. The Estes Condor (see: http://www.semroc.com/Store/scripts/ClassicParts.asp?ID=134 [Semroc also makes its parts]) is another good one; being a parasite B/G that rides on the back of a large booster, it has straight and stable ascents.

I hope this information will be helpful.

Joe Wooten
07-20-2013, 11:09 AM
I have had very good luck with the mini Dactyls. They are easy to build and trim.

aeppel_cpm
07-20-2013, 07:00 PM
A Hummingbird clone flyway prompted this thread. I built it using the above recommended sites/plans, plus PDFs of the printed colors from another thread here at YORF.

I printed the parts with a laserprinter on wholesheet label stock, stuck it to heavy fiber file folders I found, and cut it out. Painted all none-printed surfaces - so a heavy glider.

Not (usually) a long flier. Fast. Makes sudden lateral moves than can make for a long walk. But it had some really cool flights - cruising level just above the orchard trees, with the delay smoke trail coming out so it _really_ looks like powered flight.

blackshire
07-21-2013, 08:49 AM
I have had very good luck with the mini Dactyls. They are easy to build and trim.Yes, that jibes with everything I've read about them; I have also read accounts about their excellent wind penetration and stability even on breezy days (they quickly point nose-first right into the wind and don't "bobble about" as many B/Gs do in such conditions). While I haven't built and flown a Mini-Dactyl yet (I'm going to order a set of Mini-Dactyl parts from Semroc next month...), I have built generally similar hand-launched gliders, and they performed as you--and the folks whose Mini-Dactyls I read about--described. Also:A Hummingbird clone flyway prompted this thread. I built it using the above recommended sites/plans, plus PDFs of the printed colors from another thread here at YORF.

I printed the parts with a laserprinter on wholesheet label stock, stuck it to heavy fiber file folders I found, and cut it out. Painted all none-printed surfaces - so a heavy glider.

Not (usually) a long flier. Fast. Makes sudden lateral moves than can make for a long walk. But it had some really cool flights - cruising level just above the orchard trees, with the delay smoke trail coming out so it _really_ looks like powered flight.Heh, heh..."With a Centuri Hummingbird, who needs Jetex?" :-) This is another B/G I'd love to see Semroc release either as a "Retro-Repro" kit or an xKit. As spectacular as your "Jetex" flights with your Hummingbird clone were (hey, it's not like you did it on purpose :-) ), using a streamer-equipped 13 mm motor mount (like the Semroc Red-Eye's) with a bit of ballast on its top end would ensure high vertical ascents--but that would lengthen the recovery walk unless it was very calm and/or you used a low-impulse mini motor...hmmm...maybe backyard flights on 1/4A3-3Ts?

aeppel_cpm
07-21-2013, 09:06 AM
The flyaway was on an A8-3. I find that no matter how straight it boosts, at the end of boost, it arches over backwards in a large loop and levels out sometime before ejection. Except the flyaway, which did a tight loop up high and then glided out of sight.

I've read about the loop over and glide behavior with another kind of ejection glider - but I can't recall which right now.

The BT-50 based Hummer Upscale I fly with an engine adapter that has a washer glued to the top. (And a streamer). Behaves the same. I think I've flown that one on a B - and fished it out of shrubs in an oak/hickory stand. Complete luck it didn't hang up higher.

I've two gliders I've had no luck with. My Ringhawk downscale does the sliding transition - but never seems to have any forward motion afterward - it just falls gently to earth. My Flying Stovepipe is great with hand tosses - but I can't get the booster to disengage.

blackshire
07-21-2013, 09:48 AM
The flyaway was on an A8-3. I find that no matter how straight it boosts, at the end of boost, it arches over backwards in a large loop and levels out sometime before ejection. Except the flyaway, which did a tight loop up high and then glided out of sight.

I've read about the loop over and glide behavior with another kind of ejection glider - but I can't recall which right now.That sounds familiar. In the chapter on boost-gliders (B/Gs) in G. Harry Stine's "Handbook of Model Rocketry," he also discussed RGs (Rocket Gliders), which don't drop *any* parts--even spent motor cases--in flight. One type of RG that he described behaves like your Hummingbird models; it has no moving parts, but relies on the burn-off of propellant in its motor to move its Center of Gravity rearward so that it will glide. This type of RG transitions to a glide quickly, flying as your models do. It could be that the Hummingbird B/G (and it is a "short-coupled" design, having its horizontal stabilizer rather close behind its wings) achieves the same Center of Gravity shift as that type of RG, causing it to arch over into horizontal flight at the end of its motor burn.The BT-50 based Hummer Upscale I fly with an engine adapter that has a washer glued to the top. (And a streamer). Behaves the same. I think I've flown that one on a B - and fished it out of shrubs in an oak/hickory stand. Complete luck it didn't hang up higher.Have you considered publishing a plans/build/fly article about it in "Sport Rocketry?" A lot of folks would enjoy it!I've two gliders I've had no luck with. My Ringhawk downscale does the sliding transition - but never seems to have any forward motion afterward - it just falls gently to earth. My Flying Stovepipe is great with hand tosses - but I can't get the booster to disengage.I'm not familiar with the Ringhawk, but I have seen the "Flyin' Stovepipe" plans online. Conceptually, it's similar to the French SNECMA turbojet-powered Coléoptère (Coleopter, see: http://en.wikipedia.org/wiki/SNECMA_Col%C3%A9opt%C3%A8re ) VTOL (Vertical Take-Off and Landing) aircraft, which was designed to utilize its annular duct/airfoil for horizontal flight. Keep trying--the Flyin' Stovepipe should turn in beautiful rocket-boosted glides, judging by the performances of paper ring gliders that I've made and flown.

blackshire
07-21-2013, 10:35 AM
For anyone who may be unfamiliar with it, here are a plan and a review of the "Flyin' Stovepipe" boost-glider (see: http://www.spacemodeling.org/JimZ/eirp_56.htm and http://www.rocketreviews.com/estes-flying-stovepipe-plan.html ), and here is an article (with plan, see: http://jetex.org/models/plans/plans-misc/article-plan-coccinellida-am-5611.html ) on what might be called the Flyin' Stovepipe's "Jetex coleopter ancestor." Also:

Regarding aeppel cpm's problem with the booster failing to disengage from the tubular glider of his Flyin' Stovepipe, a more loose coupling between the booster's fin tips and the inner wall of the glider (perhaps using dowel "hooks" that engage launch lug "loops," similar to the way the "parasite" gliders in the Estes Condor, Firefly, and Orbital Transport kits are affixed to their boosters) would facilitate separation of the booster from the cylindrical glider at ejection.

JohnNGA
07-21-2013, 10:51 AM
I built this 2/3 scale Coaster Centauri a while back and thought that it would be my least performing glider. Boy was I wrong, at a club launch I put it up on a C6, at ejection it caught the wind and went around 300' downrange, it would still be going if the wind had not settled.

blackshire
07-21-2013, 11:11 AM
I built this 2/3 scale Coaster Centauri a while back and thought that it would be my least performing glider. Boy was I wrong, at a club launch I put it up on a C6, at ejection it caught the wind and went around 300' downrange, it would still be going if the wind had not settled.I'm pleased to read it, but not surprised. My Cox Space Shuttle America did that once on a windy day--the two gliders went considerably farther (surprisingly, even farther than the parachute-equipped core booster) than I cared to walk! :-)

K'Tesh
07-21-2013, 11:40 AM
It was either here or on TRF that I read about a method of coloring a boost glider. I have yet to try it myself on a glider, but I can say that it works for balsa nosecones.

http://farm8.staticflickr.com/7367/9336768814_a6ea6ee1e0.jpg (http://www.flickr.com/photos/94793351@N08/9336768814/) http://farm3.staticflickr.com/2832/9336767900_24a8f83df2.jpg (http://www.flickr.com/photos/94793351@N08/9336767900/)

Take a packet of RIT Dye (the tie dye stuff), and dissolve it in 91% rubbing alcohol. Then you brush this over the area you want colored, and allow the alcohol to evaporate off. The dye and the salt remains, but the lack of water doesn't affect the balsa much. Once you knock off the salt, the results are fairly even.

HTH
Jim
.

blackshire
07-21-2013, 12:07 PM
Interesting... Even if perspiration (say, from handling such a model out on the flying field on a hot day) causes the dye to "wick off" (which it may not--I don't know), more dye could always be applied as you described. Another thought: This coloring method might be good for use in some group model rocket-building sessions, especially with younger kids, because it should dry faster than paint.

aeppel_cpm
07-21-2013, 01:12 PM
There's an article on Apogee's site about using RIT on balsa.

I have an idea for an alternative Stovepipe booster, but I want to build and fly it before I talk about it. I like the post and lug option.

What kind of wire makes the landing skid on that Centuri? I've been looking for something like that as I further upscale the Hummingbird.

JohnNGA
07-21-2013, 03:02 PM
I'm pleased to read it, but not surprised. My Cox Space Shuttle America did that once on a windy day--the two gliders went considerably farther (surprisingly, even farther than the parachute-equipped core booster) than I cared to walk! :-)

I know, my old knees (even with a new one) don't care much for the cross country treks. Fairbanks, We lived there 55-56. I was only 5 but still rember the deep snow.

JohnNGA
07-21-2013, 03:04 PM
There's an article on Apogee's site about using RIT on balsa.

I have an idea for an alternative Stovepipe booster, but I want to build and fly it before I talk about it. I like the post and lug option.

What kind of wire makes the landing skid on that Centuri? I've been looking for something like that as I further upscale the Hummingbird.


Made that skid with music wire, don't remember the size (.035 maybe). Hobby shop should have it.

Bill
07-21-2013, 05:06 PM
Keep tossing and adjusting until you get it flying the way you want. Then go launch. It helps to have a 4' rod or take your 3' rod and tape it to a 3' dowel stuck in the ground. That allows the glider to have more usable launch rod length to guide it and gives you a much better boost.


A second parallel rod is useful as an umbilical to tape the clip leads out of the way of the glider's wings and tail.


Bill

blackshire
07-22-2013, 05:59 AM
There's an article on Apogee's site about using RIT on balsa.

I have an idea for an alternative Stovepipe booster, but I want to build and fly it before I talk about it. I like the post and lug option.Thank you. Also:I know, my old knees (even with a new one) don't care much for the cross country treks. Fairbanks, We lived there 55-56. I was only 5 but still rember the deep snow.It (the Cox Space Shuttle America "glide-off") wouldn't have been so bad if it had happened here; it happened in Miami, with the Sun out like a billion candles! :-)