In response to the post above, 40 seconds for a SciOly backslider flight duration is extremely unlikely. Troy's first place time at the SoCal State finals in 2004 was 27 seconds. It was a perfect design and a perfect flight under ideal conditions. I have witnessed hundreds of SciOly backslider launches and have never seen a flight longer than Troy's gold medal flight, even at Nationals in 2005. I am talking about Troy HS of Fullerton, California, and that high school has been the National overall champion seven times as I recall.
I don't want students to be disappointed if they don't get 40 second backslider flights. Any flight time over 15 seconds was typically very competitive for a 1L or 2L backslider bottle rocket.
Before the Egg - O - Naut event, when parachutes were allowed in the Bottle Rocket event, the rules required that the entire rocket be recovered with the parachute to obtain max points. Times above 40 seconds in the old Bottle Rocket event were extremely rare, even at the most competitive competitions. This was true even though the old Bottle Rocket event did not require the launch and recovery of an egg. A complete 2L bottle rocket weighs much more than an "egg capsule" under the Egg - O - Naut rules.
Any flight time over 20 seconds was competitive in the old Bottle Rocket event when parachutes were allowed. Don't start thinking you are a failure if you are not getting one minute flight times if the 2011 Bottle Rocket event rules are similar to the old Bottle Rocket event rules that allowed a parachute. Such a flight would require a lucky encounter with a major thermal. I recall that Troy (CA) got over one minute at Nationals in the late 90's.
I have no connection with Troy HS (CA) but have great respect for its SciOly program and its students.