Starhawk "de-rating?"

[blackshire]

Hello All,

A few days ago I received a Quest Starhawk kit as part of a multi-kit order from them. The original version of the Starhawk (and the Antari, a physically identical kit with a different decor scheme) used the old MPC Tomahawk plastic fin unit, whose plastic "fin can" cylinder was in direct contact with the model rocket motor. Because the heat from longer-burning motors might melt the "fin can," the kit card and instructions recommended only the A6-4.

The newer version of the Starhawk (which my kit is) uses a new fin unit that slides over the outside of the T-20 (20 mm diameter) body tube. (I've seen this later version of the Starhawk and Antari at least as far back as the 2006 Quest Catalog.) The fin unit's plastic "fin can" is separated and insulated from the motor by the body tube and an 18 mm motor mount "sleeve" tube that is glued inside the rear end of the body tube.

In the 2006 Quest Catalog, the recommended motors for the Starhawk were the A6-4, B6-4, and C6-3 (for the Antari, they were A6-4, B6-4, and C6-5). In the 2008 Quest Educator's Catalog, the recommended motors for the Starhawk were the A6-4 and B6-4. In the 2010 Quest Catalog, however, only the A6-4 is recommended for the Starhawk. Is this a typographical error, or do the latest Quest motors emit more heat than the earlier ones? (The latest ones do have thinner-walled casings.)

Many thanks in advance to anyone who can shed light on this.

[SCE to AUX]

I fly a LOT of Starhawks with our local homeschooling group, and we haven't had any problems with melting fincans. All our rockets have been the newer "insulated" version. We generally use Estes engines. The kids at our "build and fly" sessions use A8-3s and B6-4s without problems. I've flown them on C6-5s, and no fincan melting on the ones that we actually were able to get back (C6-5 might be on the recommended engine list, but it's really too much motor for this little rocket unless you have a HUGE field). I stuffed an Aerotech D21 single use motor in one, and I think that thing might have reached LEO... :D

[Shreadvector]

From my memory and experience only - actual answers should be obtained from Quest.

C6 recommendation was an error. That was corrected in later publications.

The new version with the friction fit fin can was designed to use both A6-4 and B6-4 and the only reason a C6-5 was not listed was because of stability. The C6 weighs too much and shifts the cg aft making it unstable (or at least unstable until it burns off propellant). We flew hundreds and hundreds of them with both motors without problems until....

At some point the nose cones got a bit light (plastic was thin) and this caused problems some of the time with the B6-4. After we saw this on random flights with B6-4 motors, we suggested everyone stick with the A6-4 or add a bit of nose weight (we provided it to folks at our launches if needed/requested). We also informed Quest of our observations and asked them to try a few themselves.

This year we got a fresh batch of Starhawks for the AMA Expo in early January 2010. They all had new thicker walled nose cones that weighed about twice what the previous thin-walled versions weighed. The quality was superior and they seem to be flying perfectly with both A6-4 and B6-4 motors.

I have not added nose weight and tried one with a Chinese C6-5, but I imagine they would fly beyond visual range and not melt. I don't suggest doing this in front of others unless you clearly explain to them that you have modified the rocket by adding nose weight and explain to them why that is important. Otherwise, people tend to simply imitate what they saw other people doing without fully understanding.

The 2010 catalog may have the B6-4 "greyed out" simply because of a mistake (i.e. it does not say "A6-4 ONLY" like the original version said so many years ago).


So, let's summarize:

Quest Starhark is superior. Fast to build. Extremely durable. Flies great.

Quest listens to you when you give them feedback and makes adjustments and improvements.

Did I mention the best igniter ever?

:D


Hello All,

A few days ago I received a Quest Starhawk kit as part of a multi-kit order from them. The original version of the Starhawk (and the Antari, a physically identical kit with a different decor scheme) used the old MPC Tomahawk plastic fin unit, whose plastic "fin can" cylinder was in direct contact with the model rocket motor. Because the heat from longer-burning motors might melt the "fin can," the kit card and instructions recommended only the A6-4.

The newer version of the Starhawk (which my kit is) uses a new fin unit that slides over the outside of the T-20 (20 mm diameter) body tube. (I've seen this later version of the Starhawk and Antari at least as far back as the 2006 Quest Catalog.) The fin unit's plastic "fin can" is separated and insulated from the motor by the body tube and an 18 mm motor mount "sleeve" tube that is glued inside the rear end of the body tube.

In the 2006 Quest Catalog, the recommended motors for the Starhawk were the A6-4, B6-4, and C6-3 (for the Antari, they were A6-4, B6-4, and C6-5). In the 2008 Quest Educator's Catalog, the recommended motors for the Starhawk were the A6-4 and B6-4. In the 2010 Quest Catalog, however, only the A6-4 is recommended for the Starhawk. Is this a typographical error, or do the latest Quest motors emit more heat than the earlier ones? (The latest ones do have thinner-walled casings.)

Many thanks in advance to anyone who can shed light on this.

[BEC]

FWIW the current Quest page on their site (http://www.questaerospace.com/itemdesc.asp?ic=1005&eq=&Tp=) says A6-4, B6-4

[Initiator001]

Hello All,

A few days ago I received a Quest Starhawk kit as part of a multi-kit order from them. The original version of the Starhawk (and the Antari, a physically identical kit with a different decor scheme) used the old MPC Tomahawk plastic fin unit, whose plastic "fin can" cylinder was in direct contact with the model rocket motor. Because the heat from longer-burning motors might melt the "fin can," the kit card and instructions recommended only the A6-4.

The newer version of the Starhawk (which my kit is) uses a new fin unit that slides over the outside of the T-20 (20 mm diameter) body tube. (I've seen this later version of the Starhawk and Antari at least as far back as the 2006 Quest Catalog.) The fin unit's plastic "fin can" is separated and insulated from the motor by the body tube and an 18 mm motor mount "sleeve" tube that is glued inside the rear end of the body tube.



I, too, recently received a Starhawk kit as part of my order to Quest during their President's Day Sale.

I was not aware that the fin can no longer was the MPC Tomahawk unit. I looked at my Starhawk kit and the fin can definately looks 'heftier' than the old MPC unit along with it sliding over a body tube.

Story. Years ago, my roommate Scott Pearce built a MPC Tomahawk model and flew it with an AeroTech 18mm E45 motor. We did recover the model and, sure enough, the fin can had melted to the motor casing.

I wonder if I have any E45s I can try out with my Starhawk... :rolleyes: ;)

Bob

[blackshire]

I thank you all very much for your replies.

Bob N21XK, 73 to you! If you have a big enough field, the Starhawk will fly very well on C6-7s (provided that nose ballast is added as Fred suggested). I once flew an Estes "X-Flyer" RTF rocket on a D21-7, and it disappeared like the special effects "blinkouts" on "I Dream of Jeannie" and "Bewitched"--one instant the rocket was on the launch pad, and the next instant it was just gone! The smaller, lighter Starhawk would be even better at vanishing.

Fred, the blow-molded "dayglo-orange" nose cone in my Starhawk kit is pretty thin-walled and translucent, and it is also very light; maybe it's the original iteration of the later variant of the kit that was made before Quest implemented your suggestion about the nose cone's wall thickness/mass? I had wondered about the model's stability margin with a "C" motor. (And yes, Quest does listen to us; they may produce a product that I suggested to Bill, and he personally thanked me for the suggestion!)

Bernard, I don't know how old that "copy" on the web page is, but I'm inclined to swing-test my Starhawk before flying it on a B6-4 in light of Fred's comment about the two different wall thicknesses (and masses) of the blow-molded T-20 nose cone. It's possible, though, that the nose cone in my Starhawk kit *is* the thicker/heavier one that Quest started making at Fred's suggestion, as I haven't come across any other blow-molded T-20 nose cones that were different in mass from this one--all of my (recently-bought) Q E-Z boost-glider kits have this "same-weight" nose cone.

In any event, I have no beef with the Starhawk kit--it's a fine beginner's model rocket. With Quest's new 13 mm motor adapter mount, youth groups (and we individual model rocketeers) can fly it more cheaply on A10-3T mini motors (and perhaps on *Quest* mini motors in the future).

[blackshire]

I, too, recently received a Starhawk kit as part of my order to Quest during their President's Day Sale.

I was not aware that the fin can no longer was the MPC Tomahawk unit. I looked at my Starhawk kit and the fin can definately looks 'heftier' than the old MPC unit along with it sliding over a body tube.

Story. Years ago, my roommate Scott Pearce built a MPC Tomahawk model and flew it with an AeroTech 18mm E45 motor. We did recover the model and, sure enough, the fin can had melted to the motor casing.

I wonder if I have any E45s I try out with my Starhawk... :rolleyes: ;)

BobWith the new "insulated" Tomahawk/Starhawk fin unit (having the body tube and the yellow motor mount tube between it and the motor), it *might* not melt if you were to try an E45 in a Starhawk (it'd need some nose ballast, being shorter than the MPC Tomahawk). I wonder if a Starhawk could break Mach 1 on an E45? (The older version that used the original MPC Tomahawk fin unit [Model Aerospace Company has these, and Quest still has the MPC Tomahawk fin units available] would have a better chance of going supersonic with its thin, sharp-edged scale Tomahawk fin airfoil sections.)

[BEC]

I looked at the Starhawk kit I acquired in an order about mid last year. Its face card has only A motor recommendations and the nose cone looks to be quite thin and light. This one has the Arizona address on the materials so I strongly suspect it's one of the "A only" versions.

The info on the web site was looked up just before I made the post earlier today....and that's from whence I copied the link in that post.

I can only imagine going beyond a B on one of these in a REALLY big field and with little or no wind.....and several sets of young eyes to watch!

[blackshire]

I looked at the Starhawk kit I acquired in an order about mid last year. Its face card has only A motor recommendations and the nose cone looks to be quite thin and light. This one has the Arizona address on the materials so I strongly suspect it's one of the "A only" versions.

The info on the web site was looked up just before I made the post earlier today....and that's from whence I copied the link in that post.

I can only imagine going beyond a B on one of these in a REALLY big field and with little or no wind.....and several sets of young eyes to watch!The owner of a store next door to my apartment building is marketing model rockets (including Starhawk kits) to the local schools. I'll mention the nose cone mass/A6-4 situation to her so that teachers and students can keep from having any "surprises" flying any of the older "light nose" Starhawks that they might get on B6-4 motors.

I didn't mean that you had looked up that page a long time ago, but rather that Quest may have uploaded old information onto their web site, rather like the way that old information sometimes gets carried forward in the instructions of updated kits. For example, the instructions of my new Starhawk kit say that plastic cement *and* aliphatic resin glue (or white glue) are required, even though it has no plastic-to-plastic or plastic-to-paper glue joints--that's a holdover from the original Starhawk kit that did have plastic/plastic and plastic/paper glue joints.

As for flying Starhawks on "C" motors with our middle-aged vision, well...we might as well fly Mosquitos or 220 Swifts, as they're cheaper to replace when they vanish! :-)

[Shreadvector]

I weighed the nose cones side by side at the AMA expo in January (using a jewlers digital scale being sold by the Tool Man). Of course, I did not write down the wieghts, but I do remember the new version is twice the weight of the old version. If I had to guess, I'll go with 3.5 grams vs. 7 grams.

[ghrocketman]

An E45 sounds REALLY good in one of these !!!!!
A fire-n-forget launch of a 18mm or 25mm diameter rocket every now and then is HUGELY entertaining. Recovering one is icing on the cake for sure.
Now if we could just get Aerotech to start producing SU 18mm E45's as well as the E25 reload for the RMS 18/20 case again that would be GREAT.....

[BEC]

I was wondering where one got an 18mm E.....:eek: