Motor eject models at NAR and Tripoli launches

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BABAR

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While it looks like these are going to be on hold for a bit, I was wondering about a perceived disapproval of motor eject models. (Maybe it is just me.). Seems like a number of kits (Mosquito and Swift) and gliders Astron Falcon and Flying Jenny are specifically designed for motor eject. I understand there are times when wildfire risks are high and Sparky motors and motor eject are prohibited, and I understand that motor eject models aren’t eligible for contest flying, but is there any official or unofficial heartburn over motor eject sport flying models at sanctioned (insured) events otherwise?
 
As far as I know the only official prohibition is in NAR competition, not sport flying. I've never seen anybody getting too exercised about a Swift ejecting its 1/2A case but anything much bigger probably isn't considered good form.
 
Your title threw me off a bit, you are asking about motor ejecting/spitting type tumble recovery models. As for motor ejecting models if its designed to fly that way, and was built that way then is should be fine UNLESS there is a safety related reason such as fire danger, motor hitting a bystander (generally rarely happens that a LPR motor is spit out over the crowd as long as the launch rods are aimed away from the spectators.
 
If I was RSO and a flyer wanted to eject a motor (for a good reason) I would have them launch from far enough out it would not be a hazard. With Mosquitos launching from the safe distance for an A motor there is a fair chance of getting bonked on the head, put it out farther.
I did an EZI-65 as a two stage with a finless booster and no parachute on booster. First stage was a fast H motor, we launched from 1000 feet and motor landed within 50 feet of launcher.
If the launch site is large nearly any configuration can be accompanied.

EZI-BO~1r.JPG
 
Ejecting a motor is generally a DQ in NAR competition, as you know.

There is nothing in the Safety Code that explicitly forbids ejecting a spent motor.

For little 13mm models I'm personally more concerned about the model itself in the case of the Swift 220 - it streamlines in and has a very sharp nose cone. The Mosquito or the new Luna Bug, not so much of a worry. Spat motor casings themselves generally tumble as they fall, unlike some of the models they come out of.

I would point a Swift 220 away from everyone if it came to one of my launches, but otherwise, I generally would not worry too much about something that intends to eject a 13mm or 18mm motor. For something bigger (as the one just above)....I'd have to know the specifics and make a decision on the field. For example one of the members of Rich's club is fond of CHAD staging models that take 24mm motors, which means dropping a bare, spent Estes 24mm casing on purpose. But they have a big range and even the LPR pads are a goodly distance from spectators.
 
For those who have flown the Mosquito, which hits the ground first, the motor casing or the rocket?
 
It's hard to say....I find it easier to see the motor casing after it's ejected than most Mosquitos. And it's REALLY hard to watch them both as often a 13mm ejection charge launches the motor quite forcefully out of the model.

The Mosquito does streamline in, so I'd expect it to hit first, actually.
 
Ejecting a motor is generally a DQ in NAR competition, as you know.

There is nothing in the Safety Code that explicitly forbids ejecting a spent motor.

For little 13mm models I'm personally more concerned about the model itself in the case of the Swift 220 - it streamlines in and has a very sharp nose cone. The Mosquito or the new Luna Bug, not so much of a worry. Spat motor casings themselves generally tumble as they fall, unlike some of the models they come out of.

I would point a Swift 220 away from everyone if it came to one of my launches, but otherwise, I generally would not worry too much about something that intends to eject a 13mm or 18mm motor. For something bigger (as the one just above)....I'd have to know the specifics and make a decision on the field. For example one of the members of Rich's club is fond of CHAD staging models that take 24mm motors, which means dropping a bare, spent Estes 24mm casing on purpose. But they have a big range and even the LPR pads are a goodly distance from spectators.

You wouldn't be referring to a former President of our club would you? ;):)
Actually I worry more about the E blackpowder motor catos than spit motor casings.
 
For those who have flown the Mosquito, which hits the ground first, the motor casing or the rocket?

Not sure I haven't every seen to many Mosquitos land, unless its the insect type and those get killed on sight.
 
I was having so much fun flying my Twin Factor at the Tripoli lauch over and over. Someone told me I could not fly it any more. I said "Really?" The reply was, " No, fly your rocket." I don't know who said it, but they were just messing with me anyway. It appeared that the ejected 13mm engine didn't present a safety hazard.
 
For little 13mm models I'm personally more concerned about the model itself in the case of the Swift 220 - it streamlines in and has a very sharp nose cone. The Mosquito or the new Luna Bug, not so much of a worry.

Being and Old Timer, I remember the Estes definitions of recovery methods from their catalogs in the 60s/70s. One of them was "featherweight" and included a line drawing of the Astron Streak. What I seem to recall from their definition is that Featherweight models should have blunt nose cones.

I have wondered why they would break their own definition by having the Swift 220 recover as "featherweight". Our club has had so many Swift models "kamikazee" the members, we are considering banning them from our launches.
 
...and the Streak was also much larger, yet not heavier, than a Mosquito or a Swift 220, so likely fell more slowly—at least more "feather-like" than the others. There the spent 18mm motor may well have gotten to the ground first. As with the others, tracking both the rocket and the spent motor casing is pretty tough, so I can't say I've ever seen this first hand.

The Luna Bug, with those draggy footpads, falls noticeably more slowly than the other 13mm models.
 
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