From: msjohnso@daisy.WichitaKS.NCR.COM (Mark Johnson)
Newsgroups: rec.models.rockets
Subject: Re: Scale rocket competition
Date: 28 Aug 92 13:29:00 GMT
Reply-To: msjohnso@daisy.WichitaKS.NCR.COM (Mark Johnson)
Distribution: usa
Organization: NCR Corporation, Wichita KS

In article <BtG4yq.H9y@usenet.ucs.indiana.edu> ntaib@silver.ucs.indiana.edu (Iskandar Taib) writes:
>Just curious.
>
>How is scale rocketry competition run? In the Model Airplane 
>world scale competitors have to have documentation (drawings,
>pictures) so that the judges can judge how true to scale the
>model is. In the old FAI Precision Scale the judges actually
>carried around scale rulers and went over all the dimensions. 
>These days there is "Precision Scale" where the judges get up
>close to the airplane and "Stand Off Scale" where the judges
>cannot get closer than 2 meters (I think) from the model.

We have several categories of scale modeling...

Scale - aka "True Scale" - much like model aircraft Precision Scale, the
judges go over the model with rulers and calipers, and measure the whole
works. Points are added for workmanship, degree of difficulty, and flight.

Sport Scale - like standoff scale, with a 1 meter standoff distance, except
that workmanship is judged from close up. 

Giant Sport Scale - Sport Scale with a minimum 10cm diameter or 100 cm 
length. 

Peanut Sport Scale - Sport Scale with a maximum 2cm diameter and 30 cm 
length.

Scale Altitude - Scale with tracked altitude added to the total score.

Super Scale - Scale with a scale launch pad added, which gets similar
detailed measurements, etc.

Space Systems - Sport Scale which adds elements simulating an actual 
sounding rocket launch:
	- assigned launch window
	- rocket must carry 1 oz standard payload
	- points are deducted for missing a 'safe recovery area'
	- points are deducted for percentage error in altitude prediction
	- launch system must be self contained, independent of other
	  range facilities

>That was for static judging. For the flying phase the judges 
>will give points for realistic flight, including the demon-
>stration of working features...bomb drops, flaps, retractable
>undercarriage, smoke...

Realistic flight garners points in scale rocketry also. Maximum *total* 
points for flight are 100 (Scale) to 200 (Sport Scale) out of a possible
1000. Damage upon landing deducts points from the flight score, and an
unsafe flight results in complete disqualification.

>Hmmm.. I'm thinking that some of those composite motors that 
>release lots of black smoke might be just the thing for scale
>JATO bottles.... believe it or not this would fall under the 
>AMA safety code. 

Are you sure about that...my reading of the AMA safety code indicates that
may not be the case.  I guess it depends upon whether the rocket motor is
attached to an airplane (OK) or launched from the airplane (no way).

You would need to make certain that your airframe could withstand the sudden
(10 msec rise time) application of 5 lbs of force at the motor mount.
This is the initial thrust characteristic of the F14 black-smoke motor.
-- 
Mark Johnson                          USnail: NCR Peripheral Products Division
E-mail:  Mark.Johnson@WichitaKS.NCR.COM       3718 N. Rock Rd.
Voice: (316) 636-8189 [V+ 654-8189]           Wichita, KS  67226
[Non-business email: 76670.1775@compuserve.com]
Newsgroups: rec.models.rockets