NAR ROCKET SAFETY CODE
#3 – I will launch my rockets with an electrical launch system and electrical motor igniters.
Note: It is illegal in every state to ignite a model rocket with a fuse.
Sometime in early-mid 1957 both Orville Carlisle and G.H. Stine developed forms of electrical ignition for model rockets. I believe that both were attempting to further separate model rockets from fireworks. Originally the Carlisle model rocket patent, as seen here, used a fuse type ignition. Neither Carlisle or Stine filed for a patent, however there were many earlier patents(see at bottom of article) that hinted at this process. It wasn’t until 1965 that Vernon Estes applied for a patent in which he received, as seen here, in 1968 specifically for model rockets.
Igniters are based on the method of converting electric energy to heat energy by resisting the free flow of electric current. When the electrical current is applied to a metal conductor it encounters resistance. The resistance is then converted to heat. a common ingredient in igniters is nickel-chromium, or as it is better known, nichrome. Nichrome heats up easily but doesn’t melt. The tips of these type of igniter usually contain a Squib. Squibs are materials that ignite and burn.
Copperhead igniters (from Aerotech) use carbon fibers as did the Quest Tigertails. Estes and Quest now use igniters with propritery formulas for their Squibs. I personally love the new Quest Q2 igniters.
Visit my Igniter Gallery here
other related patents
|Patent Number||Title||Issue date|
|720073||ELECTRICAL FUSE HEAD AND FUSE||Feb 10, 1903|
|1935495||SLOW MATCH COMPOSITION||Nov 14, 1933|
|2437153||(unknown)||Mar 2, 1948|
|3363559||RESISTANCE FUSE WIRE||Jan 16, 1968|
|3422763||ROCKET ENGINE IGNITER||Jan 21, 1969|
|3447416||ELECTRIC INITIATOR||Jun 3, 1969|
|4584925||Underwater rocket launcher and rocket propelled missile||Apr 29, 1986|
|4951570||Electrically activated detonator with pyrotechnic device receiving terminals and method of making||Aug 28, 1990|