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Note that for NARAM-46, theEggloft Altitude event for A Division is C engine class, whilefor B, C, and Team divisions it is D engine class.
Eggloft Altitude combines the challenge of flying a modelcontaining a Grade A Large egg (and recovering it intact), withtrying to reach the highest altitude possible.
Eggloft Altitude models can be staged. If the egg is not returnedor is damaged (cracked, broken, etc.), the flight isdisqualified.
You can NOT catch the egglofter, it must be allowed to landnaturally.
For the full rules for this event,please see the EggloftAltitude Rules on the NAR web page.
Scoring - For Eggloft Altitude, the scoring is best SINGLEqualified flight 's altitude (egg returned intact), of the twoflights allowed.
Design considerations - &endash; Balance the ability to flya model containing an egg as high as possible with the need to returnit safely. Compromises of low drag and low model weight, protectingthe egg (capsule and cushioning), and deploying a chute that is notbig enough for a gentle landing versus too big a chute which can jaminside the tube or let the model drift away unrecovered.
An egglofter with a long tapered conical shroud is OK for eggloft altitude. The Two Minute Egg plan is such a model, and both ASP and QCR have similar contest oriented kits. A straight body-tubed model with capsule on top also is competitive. Such as an all-18mm body for C Eggloft, or all 24mm body for D Eggloft. QCR has kits of this type. Custom Rockets' Elite Egglofter kit is a reasonable C eggloft altitude model. Some competitors feel the straight body type flies higher, while some prefer shrouded bodies. Straight bodies have simplicity going for them, while shrouded bodies have reliability in their favor due to the recovery system storage space and room for tracking powder. A straight body tube with a larger diameter, such as 1.3" to 1.65" diameter (BT-55, 35mm, BT-60) can be used. The model will be draggier and usually heavier, of course, and therefore at a competitive disadvantage. The Quest "Courier" egglofter kit can be used for C Eggloft, also for "D" eggloft if built with a 24mm engine mount. Some regular models you might already have can be adapted to fly as an eggloft altitude model by replacing the nose cone with a capsule. But they cannot be too heavy or they just will not fly safely enough with the added weight of an egg. | Straight tube (Prangroc) | Conical Shroud (2 Minute Egg) |
A list of plans and kits is included furtherdown on this page.
Build well - A key to any altitude event is building themodel to fly straight and true. Work towards attaching all of thefins so they are straight and parallel to the body. This shouldtranslate to a straight boost, with minimal wobbling that would hurtthe altitude.
Egg Capsule - PrattHobbies makes an excellent vac-formed egg capsule (the old CMRcapsule). Some companies like ASPand QCR carry thatcapsule. Apogee also hastheir own vac-formed egg capsule.
Another capsule sometimes used is a plastic Easter Egg, of a sizethat is just a little bigger than an egg. Such capsules use two "longhalves" from two 1.75" diameter Easter eggs, rather than one plasticegg due to the short half with a flange sticking out, as the flangelimits the inside diameter too much. Easter Egg capsules that smallcan be hard for the eggs to fit in and be safely cushioned, however."Grade A Large" eggs tend to vary significantly in diameters, soEaster Egg capsules are somewhat risky. It's best not to risk using atoo-cramped capsule.
Padding - Use foam or some other flexible material to tryto cushion the egg so it will not get cracked. My favorite basiccushioning is to get hold of a foam egg carton and cut out the fourcorner "cups" as they fit the egg pretty well. I add other thin foampadding as well. The egg needs to be padded enough that it can'trattle, but don't pack it so tight that it's under pressure whenloaded in the capsule. If you are using a plastic capsule, don'tbother with putting the egg inside of a plastic bag....if the eggbreaks you can just clean the capsule with water, without anydamage.
Parachute - In Eggloft Altitude, the trick is to balance using a chute size that will not land so hard that the egg might crack, versus using a bigger chute that may let the model drift too far off to recover. A ballpark suggestion for decently padded eggs in a light model is to use a 12" to 14" parachute. For eggloft Altitude, using a commercial type chute canopy is usually OK, you don't want to use a canopy so thin that it rips easily.
Shroud lines can be "button and carpet thread", which is what most manufacturers use. To avoid the lines pulling loose from the parachute under stress, the shroud lines can be attached to run over the top of the chute as shown at right. Cut-up band-aid pieces can make for very sticky yet flexible shroud line tabs. |
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Engine recommendations for C Eggloft Altitude (A Division): | C6-3 (somewhat heavy or draggy model) |
or | C6-5 (low drag light model) |
or | C6-7 (high performance low drag light model, if not too windy) |
Engine recommendations for D Eggloft Altitude (B/C/T Div's): | D12-3 (heavy and/or draggy model) |
or | D12-5 (low drag lightweight model) |
or | D12-7 (high performance low drag lightweight model if not too windy) |
or | C6-0/C6-7 staged (Low drag lightweight model if not too windy)* |
* Staging C's is a fairly high risk way to fly D Eggloft Altitude, not really recommended. |
Model Plans & Kits | Designer | Notes |
ASP - Egglofter Kits (various) & Pratt Egg Capsules | ASP (Aerospace Specialty Products), Andy Jackson | Good competitive kits |
QCR - "Easter Egg" & "Pratt " capsule Kits for 18mm & 24mm engines. | QCR - Qualified Competition Rockets, Ken Brown | Good competitive kits |
C & D Egglofter Plans - straight tube type | Plans by George Gassaway | Competitive plans for C and D power, minimal details |
Prangroc plan straight tube type (NAR website) | Plan by Mike Burzynski | A very old straight body tube design, showing how plastic Easter Egg capsules could be used. Modern-day suggestion would be to use BT-20/18mm body tube and Pratt Egg capsules |
E Dual Egglofter plan straight tube type (NAR website) | Plan by Glenn Feveryear | The basic 24mm body of this dual eggloft plan can be used with any practical egg capsule for D single Eggloft altitude. |
2-Minute Egg Plans shroud type (NAR website) | Plan by George Gassaway | Good competitive plan for C power (shroud) |
Elite Egglofter kit by Custom Rockets | A reasonable model for C Eggloft Altitude | |
Shecter Rockets Egglofter kits (PDF list) | Fred Shecter | Straight tube (18mm) egglofter kit with Easter Egg type capsule. Fins shown seem much bigger than necessary. |
QUEST - "Courier" sport egglofter kit | QUEST - Model Aerospace Company | Not too competitive, but flyable on a C6-3. Available from various Quest dealers, including Apogee |
by Andy Jackson, on the ASP (Aerospace Specialty Products) website | Great article on considering what size or type of parachutes to use in egglofting competition, whether for duration or altitude. Also tips on chute packing. |
Last Updated 4/19/2004