Monday, May 18, 2015

A Geezer's thoughts on the 2016 TARC challenge...

Well, the 2015 TARC finals are over (Yay Russellville! Have fun in Paris!) and the 2016 rules are out. I look forward to a new challenge each year, and this one has some interesting twists. So, good readers, below is a short summary of the TARC 2016 challenge, with my thoughts on some of the more interesting aspects of the competition.
  • Payload is two eggs (one oriented lengthways, one sideways) - this is a evil move by TARC, for a couple of reasons:
    1. If you do not have good protection and separation of the eggs, the lengthwise egg will drive right through the horizontal one. Eggs have decent strength along their long axis, but are very fragile along the short. I foresee many messes in the coming season.
    2. The sideways egg forces designers/builders to a BT-80 tube (or larger) for the payload section - past years could use the smaller BT-70. Larger diameter = greater surface area = more drag.
  • Altitude goal for qualification flights is 850 feet - this is higher than this past year's 825 mark, and you have twice the payload (2 eggs) + greater drag. It is theoretically possible to do this on E impulse, but I suspect many teams, even those that build light, are going to have to resort to F's or the equivalent. Greater impulse = more expensive motors.
  • Total flight duration must be between 44 and 46 seconds - 2 seconds shorter than last year, so the rocket must descend faster. Again, better have good egg protection!
  • The very tiny Perfectflite Firefly (see my Nov 30 post) joins the PNUT and APRA as an official altimeter.
  • Rocket must be at least 25.6 inches (65.0 cm) long and weigh less than 22.9 ounces (650 grams) fully loaded - same as last year.
  • All parts of the rocket must recover as a single connected unit (payload section cannot come down separately). Any type of recovery device may be used, as long as the rocket lands safely. Trip Barber and other NAR folk think this could get interesting; I think many folks will opt for ye olde conventional parachute. Kinda risky to get creative with 2 eggs waiting to become omelets.
  • Scoring, number of flights, etc. are the same as last year.
That's the challenge for the kiddos. And now...

We have also canonized the Geezer TARC rules for 2016, which are the same except for the following:
  • Geezer TARC begins with the announcement of the 2016 rules in May and ends with the contestants’ rockets being launched at a single event (date TBD, but well before school starts in late summer).
  • Each contestant may enter up to two rockets. These rockets may not fly before the official launch date, and the score shall be determined by the first flight of each on that date. The contestant's score shall be the better of the two flights, or the score of one flight if only one rocket is entered.
  • Any commercial altimeter may be used to determine altitude. However, reflights are not allowed if there is an altimeter malfunction; in this case, the flight will be disqualified (So choose a reliable altimeter).
  • There is only one rocket per design, and there are no test or sub-scale flights permitted for the design. Its merit will be judged solely by the rocket’s performance at the contest launch. If two rockets are entered, they must be of substantially different design - different number of motors, fins, or something major - an inch shorter or taller does not constitute a substantial difference, nor does the same design at a different scale (e.g., BT-70 versus BT-80 versions).
So how I am going to meet this year's challenge? Well, I have already have the first design, and the parts to build it - once I have made a couple additional tweaks. I don't want to give the competition any tips, but I can say this much:

This rocket ain't going to use a single stinking F motor!

After all, I have a rep to protect...

1 comment:

  1. I look forward to getting my hands dirty, hopefully not with egg. Also check this out.