ERAU-Prescott flies liquid rocket to 47,000ft*
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- เผยแพร่เมื่อ 31 พ.ค. 2023
- *Rocket was lost on return. Only the nosecone survived.
April 15, 2023
Cygnus Suborbitals, the liquid bipropellant launch team from the Rocket Development Lab at Embry-Riddle Aeronautical University, Prescott, was able to launch their substantial KeroLOX rocket "Deneb" to 47,000ft. Since the vehicle was lost after a recovery failure, the current altitude record for successful liquid bipropellant launches arguably remains at 22,000ft by UCLA Rocket Project, but this launch marks a milestone for propulsion potential.
Unlike the UCLA rocket, Deneb boasts around four times as much propulsive impulse in it's propellant tanks, and the advanced composite wound ablative motor provides four times as much thrust. Fitting this motor and the required plumbing into a vehicle that is both narrow and strong enough to survive flight is only the result of good design and development. The tidy exterior is a testament to the high quality hands-on work and attention to detail.
Despite the rocket and the team performing excellently on ascent, the vehicle was lost following ballistic return. This is important as, while the vehicle flew rather high, it was only a partially successful mission. There is some debate on whether to honor crashed rockets for Liquid RLV apogee records, and I am of the opinion that focusing so much on records fails to respect the unique challenges and achievements of rocket teams and their individual means, of which they are not equal. While the significance of these records should not be overemphasized, they should still give due credit to successful flights as a matter of course. We may need to keep track of separate records for pure altitude as well as successful flight, but tracking altitudes for rockets in which the altimeters are destroyed and telemetry often lost is inconsistent and unreliable. Let me know what you think about this in the comments. - วิทยาศาสตร์และเทคโนโลยี
I was on the team that launched the rocket. We confirmed over 47000ft on all avionics (Telemega, EasyMini, Featherweight GPS, SPOT Trace). These were all recovered in the nosecone.
The current theory is that the nosecone deployment at apogee was violent enough to break the main parachute retention device. The main parachute then deployed at a higher speed than nominal causing the sewn-on loop in the drogue shock cord to break off, resulting in the nosecone and main separating from the rest of the rocket and the drogue. The main body of the rocket either impacted ballistically or under drogue. We are hopeful that we will find the rest of the rocket in the near future since we have a good idea of where it landed.
Thanks Derek for the awesome shots!
Recovery is always difficult, but this sounds like it the problem has been identified and it can be addressed in the next rocket. UCI recovered the remains of their rocket in surprisingly good condition using drone footage, but there was a lot of rain last week.
so cool! Do you have any resources I might be able to look at to learn more about this rocket/engine/design process? I am trying to work towards a liquid biprop rocket with my rocketry team in Eastern VA.
An interesting note on the actual rocket flight, the pressurant tank was only at 2400/5000 psi at launch due to a fairly severe nitrogen leak, after looking at data from previous hot fire attempts, factoring in our leak rate, and looking at acceleration data we hit about half the nominal expected burn time. We’ll be back with a rebuilt Deneb, and new recovery hardware, soon enough to push the altitude farther, and hopefully hit a projected altitude of ~90,000 ft.
Great video, and cool camera angles.
I'm glad to hear that. Deneb was a fine rocket. Build it again, and it surely will. Keeping 5000 psi in the tank will be really tricky.
Good work
hell yeah lets go riddle
Nonetheless, impressive!
Good explanation. Thanks. If the altimeter data can be plotted and published that sure would be nice.
Derek, how did ERAU determine the altitude was 47,000 feet? Big claims should be backed up with data.
That's one of the reasons that I separate raw apogee from recovered flights, but it just so happens that the altimeters survived the flight in the nosecone, which coasted three times as far horizontally as it did vertically without the vehicle attached. The rocket itself is believed to have buried itself in the lakebed. It was almost like a low altitude satellite deployment by an expendable launch vehicle.
The 47kft said in the video was read out by the Featherweight GPS ground station. When we got the nosecone back a couple of weeks ago, the data pulled from the Featherweight said 47,690ft, and the Telemega said 47,700ft.