Centuri X-24 Bug

[Ironnerd]

I have built a couple of these in boiler-plate form, and a Quest HL-20. Now I want to build a X-24 correctly. Does anyone have the dimensions for the X-24 Nose cone? I can get everything but that. My boiler-plates just had a flat nose (I figured, correctly, that there would be some nose-trauma until I got the CG location figured out).

Thanks.

[gpoehlein]

Cloning the Centuri X-24 Bug is really easy - use the nosecone from the Estes Yankee. It is an "Estes-ization" of the Centuri nose cone. I built one and I used foamcore for the bulkhead. It flew great, but it isn't real robust - after five or six flights it started to warp and I need to build a new one.

I really liked the Centuri newsletter (it may be on Jimz) that showed building a Saturn V and putting the Bug on top like a nose cone - the booster came back via chutes while the Bug ejected and glided in.

Greg

[Doug Sams]

Cloning the Centuri X-24 Bug is really easy - use the nosecone from the Estes Yankee. It is an "Estes-ization" of the Centuri nose cone. I built one and I used foamcore for the bulkhead. It flew great, but it isn't real robust - after five or six flights it started to warp and I need to build a new one.Greg,

In my experience, the plastic NC was a bit heavier, just heavy enough to make the already difficult trimming that much more difficult :)


I really liked the Centuri newsletter (it may be on Jimz) that showed building a Saturn V and putting the Bug on top like a nose cone - the booster came back via chutes while the Bug ejected and glided in.That's one of those projects I've been thinking about for years. I have some BT100 and some BT101. I was thinking of building a quasi-Little Joe2 and using a g-timer to start the Bug and/or HL-20 topping the stack.

I need to order some custom rings. That's about the only tricky part of the build.

Doug

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[Doug Sams]

I have built a couple of these in boiler-plate form, and a Quest HL-20. Now I want to build a X-24 correctly. Does anyone have the dimensions for the X-24 Nose cone? I can get everything but that. My boiler-plates just had a flat nose (I figured, correctly, that there would be some nose-trauma until I got the CG location figured out).FWIW, you can order a balsa version of that cone. It's a little lighter and hence a little easier to trim. Also, Squirrel Works makes a very similar bird in their X-RV (http://www.squirrel-works.com/catalog/xrv/xrv.html). You might consider that as well.

Doug

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[Ironnerd]

A few minutes after I posted this, I stumbled on the answer. Of course it took a while longer to figure out the Estefied Nose Cone number. Semroc has them in balsa, so I may have to order a few.

Thanks for the help guys.

[Earl]

BRS Hobbies (BRS.com) has the Estes PNC-20Y cone (their knockoff of the original Centuri plastic cone) for like $1.25.

Been looking at those for an Eneret Athena clone (it would use eight of those cones).

The Semroc balsa version would probably make trimming a bit easier, but will not hold up quite as well to hard landings and dings.

The X-24 always made for some interesting flights. I remember trimming mine as a kid by tossing it out an upstairs window into the front yard. Of course as fate would have it, one of the first tosses had it headed in a bit of a nosedive towards the concrete driveway. That's how I 'know' about nosecone dings.... :o

Earl

[Ironnerd]

I trimmed mine by tossing it down the stairs into the basement.

I actually got the HL-20 to fly pretty well, then I tried flying it on a "C" and it ventured off into the trees and vanished.

I have had quite a bit of fun with cones. They glide (sort of) and are nice for small fields.

Thanks fior the info. I'll check BRS and compair to Semroc. I'll proabably end up getting one of each and compairing performance and trimablility.

Other than the nose cones, the things are DIRT cheap, and have an axcellent cool factor rating.

[Cohetero-negro]

I have built a couple of these in boiler-plate form, and a Quest HL-20. Now I want to build a X-24 correctly. Does anyone have the dimensions for the X-24 Nose cone? I can get everything but that. My boiler-plates just had a flat nose (I figured, correctly, that there would be some nose-trauma until I got the CG location figured out).

Thanks.

Iron,

The Bug has a GREAT HOWLING sound going up ... but its glide is well I guess you can call it a glide as long as it moves forward a little bit as it drops!

There was a guy cloning those and I think if you keep an eye out on ebay, you might snag one.

I remember the nose cone for the bug was a red plastic cone that Centuri used. I am sure Semroc has a clone cone for you. As has been listed here, you can get the cone easy.

Please post a picture of the model and your fight report with it!

Jonathan

[Doug Sams]

The Bug has a GREAT HOWLING sound going up ... but its glide is well I guess you can call it a glide as long as it moves forward a little bit as it drops! You can fly them on C6's, but you gotta watch those C5's ;)

http://www.doug79.com/x24-bug/X24-3-2.jpg

Here, under the thrust of the C5, the drag forces collapsed the sides of the airframe into the motor exhaust. Not pretty. This one was really howling...'til it caught on fire :eek:

Doug

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[Cohetero-negro]

Doug,

Looks you had a 'blow out in vapor 3'! ?

Did you try to contact Flight Com and report that she was 'Breaking up! Breaking up!' :)


http://upload.wikimedia.org/wikipedia/commons/1/10/M2-F2_crash.jpg

http://upload.wikimedia.org/wikipedia/en/b/b7/Sixmilliondollar1.jpg

J

[Cohetero-negro]

Movie Intro ... I can't get to youtube from work so would someone post the youtube link of the TV show, or I will just do it later when I get home:

http://www.schooltube.com/video/f0ec8d757e2a6d85768e/Six-Million-Dollar-Man-TV-Movie-Intro

[Cohetero-negro]

Here is the link :)

www.youtube.com/watch?v=HofoK_QQxGc

[blackshire]

You can fly them on C6's, but you gotta watch those C5's ;)

http://www.doug79.com/x24-bug/X24-3-2.jpg

Here, under the thrust of the C5, the drag forces collapsed the sides of the airframe into the motor exhaust. Not pretty. This one was really howling...'til it caught on fire :eek:

Doug

.
.Hmmm...a semi-monocoque structure (the existing "dihedraled" card stock cone stiffened and strengthened with balsa or carbon fiber formers and stringers glued to the inside of the card stock) might enable C5-3 or even composite D10 powered flights. To save weight, the round-cornered fiber triangular cone "dihedral" former plate could be replaced with a narrow former "ring" of the same outer perimeter shape, which could be attached to the motor mount tube using a few radial tie beams.

[blackshire]

Doug,

Looks you had a 'blow out in vapor 3'! ?I think it was "damper 3" (the yaw or roll damper, I believe). The pilot for that flight, Bruce Peterson (see: http://en.wikipedia.org/wiki/Bruce_Peterson ), was having problems with the M2-F2's roll response during the landing approach, and that combined with a pilot-distracting maneuver to avoid colliding with a rescue helicopter in or near his descent path contributed to the crash. The M2-F2's landing gear weren't fully extended when the lifting body touched down, which caused the high-speed rollover crash that very nearly killed Peterson outright and later resulted (via a secondary infection) in his loss of sight in one eye. Amazingly, he recovered and continued his research flying work for NASA (see: http://en.wikipedia.org/wiki/Northrop_M2-F2 ).

I've always thought that the Northrop M2-F3 (the modified, rebuilt M2-F2 with a third vertical stabilizer, see: http://en.wikipedia.org/wiki/Northrop_M2-F3 ), the Northrop HL-10 (see: http://en.wikipedia.org/wiki/Northrop_HL-10 ), the Martin Marietta X-24A (see: http://en.wikipedia.org/wiki/Martin_Marietta_X-24A ) and X-24B (see: http://en.wikipedia.org/wiki/Martin_Marietta_X-24B ), and the Martin Marietta X-23A/SV-5D PRIME (see: http://en.wikipedia.org/wiki/Martin_X-23_PRIME ) would make interesting scale boost-gliders. Models of them could be made of vacu-formed styrene or styrene foam (which could be covered with Kevlar "veil" and epoxy to make the surface more durable) with sheet balsa vertical stabilizers. They could "hitch-hike" on longer and larger existing rockets as parasite boost-gliders.

[Cohetero-negro]

Yes it was 'Damper 3'! Good catch!


One of the greatest TV shows ever made!

J

[blackshire]

Yes it was 'Damper 3'! Good catch!Thank you.One of the greatest TV shows ever made!

JIndeed! They used actual bionic arms (not having super-human strength, of course) for the "bionics checkup and repair scenes" with Dr. Rudy Wells. Lee Majors had his real arm stretched and tied behind his back and he wore the bionic arm during those scenes. Even as early as about 1970, there were already bionic hands that would pass for their flesh-and-blood counterparts at a casual glance, and they were dextrous enough to allow their possessors to use them to tie shoelaces. My favorite line is from one of the early pilot TV movies. After Steve Austin rescued a woman and her boy, she noticed a few wires protruding from the damaged skin of his bionic arm and asked him, "Who are you...*what* are you?!"

[Ironnerd]

I have had one cone collapse on me. It was, most likely, the dreaded Krushnic effect. To address the issue, I made six longerons from 100lb card stock. They are accordian folded, then glued inside the cone so then look a little like this -^-

They add a touch of weight, but I have never had one collapse since.

To avoid excessive charring on the interior, I stuff some "dog barf" wadding into the front end of the engine. Seems to work prety nicely - actually makes a big difference.

For the fusealge that does get burned (I launched a few on booster engines), I just printed a new shroud on copier paper and glued it over the old damaged shroud.

I don't use a launch lug, per se, I cut a oval hole near the nose, and put a notch in the bulkhead. These serve as a luanch lug that runs along the motor tube, and allows the rocket ro take of going straight, as opposed to an angle.

I also use a 24mm motor mount - not that I use 24mm motors. I have an 18mm motor adapter with a streamer wrapped around it, Whenthe motor kicks out, it comes down on a streamer (NAR-friendly).

Lastly, I found that the X-24 is easier to trim without the fins.

[Eagle3]

.... This one was really howling...'til it caught on fire :eek:

Doug


Oh, I think it was howling after it caught fire too. ;)

Buzz

[Earl]

Thank you.Indeed! They used actual bionic arms (not having super-human strength, of course) for the "bionics checkup and repair scenes" with Dr. Rudy Wells. Lee Majors had his real arm stretched and tied behind his back and he wore the bionic arm during those scenes. Even as early as about 1970, there were already bionic hands that would pass for their flesh-and-blood counterparts at a casual glance, and they were dextrous enough to allow their possessors to use them to tie shoelaces. My favorite line is from one of the early pilot TV movies. After Steve Austin rescued a woman and her boy, she noticed a few wires protruding from the damaged skin of his bionic arm and asked him, "Who are you...*what* are you?!"

Just saw an infomercial tonight advertising the first season of the show on DVD for the first time ever. Put out by one of those Time-Life deals. Price was $39.95. Included several of the pilot movies as well. I was not a super-big fan of the show as a kid, but for those who were, looks like you'll be able to finally re-live those memories.

Earl

[blackshire]

Just saw an infomercial tonight advertising the first season of the show on DVD for the first time ever. Put out by one of those Time-Life deals. Price was $39.95. Included several of the pilot movies as well. I was not a super-big fan of the show as a kid, but for those who were, looks like you'll be able to finally re-live those memories.

EarlEarl, thank you for posting this!

[mycrofte]

I have looked but can't find the tube length for the X-24. Anyone have it handy?
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[Ironnerd]

I have looked but can't find the tube length for the X-24. Anyone have it handy?

See the attached documents.

All parts are from Semroc

Streamer wraps around the BT-20J between the two CR's. Do not GLUE the CR's to the BT-50J.

After all the glue is dry, apply Superglue to the CR's, allow to dry, sand smooth. This will provide a much more durable surface.

[mycrofte]

The plans on Jim Z's looks like it's just a rear ejection. I didn't think there was any more to it.

But, if I dig in the garage, I should have all of that.
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[Ironnerd]

The original X-24 did just eject the motor. I made a few changes to make the model more "NAR Friendly", and field owner friendly. No one wants to get bonked in the head with an expended motor casing, and field owners frown on finding little paper tubes left behind by "those rocket people".

It looks like a 3.75" piece of BT-20 will work for the motor tube if you just want to go with the original plans. The things are REALLY stable, so having the motor a touch aft will not cause much of an issue.

Be sure to put some "dag barf" or recovery wadding in the top of the motor - helps prevent burns from the ejection charge.

[mycrofte]

When I make a rear ejection I glue a piece of aluminum foil to the nose cone as a shield. Never thought of packing anything on top before.
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[Ironnerd]

The wadding seems to soak up some of the hot/glowing bits. When I was launching them as straight-up rear eject, I had a few "cigarette burns" in the cone. Wadding seems to have fixed that issue.