----- Original Message ----- From: "[email protected]" <[email protected]> To: "i8cvs" <[email protected]> Sent: Sunday, September 22, 2013 5:01 AM Subject: Re: [amsat-bb] Re: Phase 3
Are you sure the kick motors on ao10/13 were solid ???? I was pretty sure the were liquid because the could be fired multiple times to tweak the orbit. I also remember seeing pictures of technicians I'm hazmat suits fueling the bird. --> Rob, ka2pbt Hi Rob,KA2PBT The solid propellant motor of OSCAR-10 was designed to fire only one time at the apogee and change the orbit inclination to around 67 degrees into a Molniya orbit but unfortunately the onboard 400 Newton kick motor did not function entirely correctly, due to collision with launch vehicle after separation - hence the not-quite-Molniya-orbit with only inclination of 27 degrees. OSCAR-13 uses a bi-propellant hydrazine and nitrous oxide 400 Newton motor system and behaved flawlessly during the two post launch burns. Oscar-13 was launched into a highly elliptical equatorial orbit, a "Geostationary Transfer Orbit", with a perigee height of 240 km. Over the next 7 days it was re-oriented to point the motor along-track such that apogee velocity could be increased by 150 m/s. This increased perigee height to 1100 km, and freed the satellite from buffeting and atmospheric drag. During the next 2 weeks it was oriented "upwards" so that a burn at apogee would increase inclination to 58°, and perigee height to 2500 km. Two weeks later, 1988 July 22 15:00 utc the mode-B transponder was switched on for general use. The pictures you have seen referes to charge the fluid bi-propellant hydrazine and nitrous oxide toxic fuel into OSCAR-13 and later on to charge the liquid propellant into AO40 made with UMDH and nitrogen tetroxide. 73" de i8CVS Domenico On Sep 21, 2013, at 22:15, "i8cvs" <[email protected]> wrote: > ----- Original Message ----- > From: "Angus McLeod" <[email protected]> > To: <[email protected]> > Sent: Saturday, September 21, 2013 9:27 PM > Subject: [amsat-bb] Re: Phase 3 > > >> As far as I know, the kick-motors used on the Phase-3 birds were NOT >> cardboard tubes packed with homemade gunpowder. They were commercial >> grade motors obtained from the commercial aerospace industry. If I am >> wrong about this, and someone can jump in with facts, I'd be glad to >> hear. > > > Hi Angus, > > The kitch apogee motors for OSCAR-10,and OSCAR-13 were solid propellant > 400 Newton trust motors donated to AMSAT-DL by the Messerschmitt Aerospace > Company in Germany. > > The kick apogee motor for AO40 was a liquid propellant made with UMDH and > nitrogen tetroxide but it failed to work because unfortunately someone > before the flight forgot to remove the safety red cover over the exost > valve of the fuel system and this is why after many attemps to overcome > the problem the satellite got an explosion inside wich damaged most part > of transponders.BTW AO40 worked fantastic in Mode U/S ,Mode L/S > and Mode L/K for a long time until the main battery and the spare battery > system suddently failed in short circuit. > > 73" de i8CVS Domenico > > > _______________________________________________ > Sent via [email protected]. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
