|
Post by Mark on May 5, 2010 16:13:04 GMT 1
|
|
|
Post by grantj on May 5, 2010 16:21:00 GMT 1
Holy Cow!!!!! Them are BIIIG Rockets ;D Which ones in the photos where yours? (for those of us who dont know what you look like other than Tintin Captain ) What sort of power do you use to launch them - Estes never had anything that size!
|
|
|
Post by Robert on May 5, 2010 20:23:10 GMT 1
Well, Chill can now say: "Goodbye Honest John, hello Black Rock!" Congrats with your Level 1 Certificate. How does it rate by the way, how many levels are they altogether?
|
|
|
Post by Achtung!! on May 5, 2010 21:47:01 GMT 1
hello Black rock!
Im now under my metal bath tub whilst I type this.
|
|
|
Post by Mark on May 5, 2010 23:24:00 GMT 1
Here's the Honest John. It was quick off the pad ! There are 3 levels. L1 is H & I class motors. L2 is J & K class motors. L3 is L & greater. The little Estes rockets are class A to D, and each letter increase represents a doubling of total impulse. L1 is simply demonstrating you can build to an acceptable quality, launch and recover the model. L2 is the same, and you have to pass a written exam. L3 is really heavy. Not many L3 kits around, so you generally have to design and build the rocket, having the design checked by other experts, and have the build checked periodically, followed by a successful flight. These things are big ! They will have a multitude of electronics, such as altimeters, electronically fired parachutes, radio trackers, cameras, etc. An L class motor will cost over £200, produces about 275 pounds of thrust, and burns out in 4.5 seconds. Anybody want to sponsor me ?
|
|
|
Post by grantj on May 6, 2010 5:58:43 GMT 1
Wow 200 pounds for a 4.5 second bang No wonder you looking for a sponsor! Roughly what is the all up cost of a rocket with motor and electronic gizmo's? Seriously though they do look very impressive and I was totally unaware that model rocketry had reached such a technological high. What are the rocket bodies made out of - carbon fibre? Do you build from plans or is it scratch built and do you have to balance them C of G wise like aeroplanes. Sorry for all the daft questions but I am absolutely fascinated by them Thank heavens they are illegal in South Africa- I dont think I could afford this hobby as well as all the others!
|
|
|
Post by Baz on May 6, 2010 9:14:10 GMT 1
Talk about a line up of weapons of destruction ...... Gotta just luvit Did that 'Eclipse' model have the word 'CHILL' written on it's base ..... Obviously Achtung's mojo worked with the Honest John ..... Someone else in the group needs to change their attack destination ...... ;D ;D ;D They looked fantastic What a whoooooosh And congrats on your certification Baz
|
|
|
Post by Mark on May 6, 2010 11:25:41 GMT 1
Thanks for all the congrats. For the big stuff you're into 4 figures. £300 for the motor casing, £400 for the electronics, probably £300 to £500 for the rocket parts. All ball park figures..... You can put a smaller High Power rocket into the air for around £150 upwards. The Black Brant kit was about £60, engine case another £50, and about £25 for the engine itself. The engine case is reusable, and there are no electronics on board. Here is a photo of the Black Brant going up on a G motor from last year. www.serfs.org.uk/cgi-bin/mediumpictures.cgi?ImageNumb=10Of course, you can get the Estes stuff from about £15 or £20 for a starter set I think. Smaller rockets, but they still go up several hundred feet, and are great fun. Kids love them. My wife and daughter often come to a launch with me. The club we fly at (SERFS - www.serfs.org.uk/index.shtml) are very family friendly and it's great seeing a big smile on a kids face when they press the button. Enough sales pitch (but anybody in the south going to join us ?) back to the Rockets. Carbon fibre is not often used. The bodies are often a resin bonded card tube (phenolic) or a plastic tube, which looks like a drain pipe but is better quality ! Fins are either ply or glass fibre sheet. You don't need to balance them like an aircraft, but the relationship between the centre of pressure and the centre of gravity is important. The C of G must be significantly in front of the C of P to ensure a stable flight. There are modelling programmes that calculate both parameters for you. Typically you would either increase the fin size, add nose weight or lengthen the body if the rocket is unstable. A rocket can also be overstable, if the fins are too big or the nose too heavy. This causes excessive weather cocking (rocket flys into the wind). Shame you cant fly them in South Africa though........
|
|
|
Post by grantj on May 7, 2010 10:48:28 GMT 1
Thanks for that info Mark It sounds absolutely fascinating and my bank manager is very glad I cant take up this hobby as well ;D
|
|
|
Post by Mark on May 7, 2010 16:19:52 GMT 1
You could always buy one as a static display piece. I happen to know that a new company is about to start producing some nice Carbon Fibre rocket kits
|
|
|
Post by mike on May 7, 2010 16:41:13 GMT 1
Thats an exciting but expensive hobby Mark. if you had the oppertunity would you go up in the space shuttle. mike
|
|
|
Post by Mark on May 8, 2010 23:34:45 GMT 1
Now there's a good question Mike, I would have done in a flash before the second one exploded. But now, probably not. Besides, my wife would never let me. She doesn't even like me riding a bike or flying a private plane (but I've sold my bike, and my PPL lapsed long ago)
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on May 9, 2010 0:09:59 GMT 1
The space shuttle has only 3 more missions before it stops flying for good, so think it would be a bit hard even if you wanted too.
|
|
|
Post by Mark on May 9, 2010 15:26:38 GMT 1
Not being a leading astronaut or scientist is also a bit of a draw back in this respect.
|
|