That's interesting. I had largely forgotten about that story down. I think there are a couple of typos/editing errors - altitude would be 100,000 feet not SR altitude + 100,000 feet and I suspect an extra zero has crept into the payload.
yes yes, but what happened to the Harassment drone w/ the Fuzz Buster and the wooden prop ? :}
Corrected - cheers.
It seems invidious to repeat; a scale of tens of metres maybe, tens of kilometres maybe not.
The British Harassment Drone is covered in Typhoon to Typhoon. It was of course over-engineered and used bespoke kit, unlike the US one with its Fuzz buster and lawnmower engine. Last time I saw a 'Fuzz Buster' was in New Zealand in 1983. Of course, I never used it. No. Never. No, it didn't warn me of the polis speed trap in Wellington. No, not at all.
A scale of tens of kilometers indicates that the aircraft has an issue that recurs on a very long timespan. If the aircraft was traveling at Mach 5 (or call it 3800 mph or 1.055 miles per second) and the distance between pulses is measured in miles, then the *time* between pulses is measured in seconds. Not fractions of a second, but full seconds. There is no engine operation that recurs that slow. A turbine spins many thousands of times per second; a PDWE goes *bang* many times per second. So a regular pulsation that occurs miles apart is not related to the rate things happen in an engine, but has to be related to something far, far slower. Perhaps ice building up on some structure; a jetliner going Mach .5 would go 0.1 miles per second, and a pulse every five miles would indicate that, perhaps, ice builds up for 50 seconds then breaks off and goes into an inlet or something.
125,000 RPM:
Yes but you said "many thousands of times per second". Even just one thousand per second is 60,000 rpms.125,000 RPM:
View: https://www.youtube.com/watch?v=jixLhz-3vXE
Also:
https://en.wikipedia.org/wiki/TurbojetAt the large end of the range, the GE90-115B fan rotates at about 2,500 RPM, while a small helicopter engine compressor rotates around 50,000 RPM.
A jet engine for some sort of hypersonic vehicle would doubtless be relatively small in diameter and spin like a maniac.
Yes, that's more like it. My first thought was a phugoid pitch oscillation brought on by shockwaves not behaving quite as the computer predicted, and the control system reacting barely fast enough.
I was 99.999% sure you meant minute but hey, gotta have some fun.
if we are all correcting history, could we correct rpms to rpm. Thank you.I was 99.999% sure you meant minute but hey, gotta have some fun.
We've all been there, less alcohol will help.
Nobody likes a grammar Nazi.
Or maybe more. That might be my problem... my lifelong refusal to indulge in mind altering substances. Maybe those are what's needed to come to acceptance with the state of the world.
Gone well off topic. Which is nice. Maybe start a new thread like Pedantry Corner in Private Eye?
I still rely on my memo writing course, courtesy of the RAF.
The "Raff"?
The "Raff"?
Who knows!!The "Raff"?
Would the Raf have operated the Aurora? Would the Uk mOd have allowed the USAF to fly it from bRitish air bases? Hmmm...
How bizarre. It's 1993 all over again
quellish said:airrocket said:Aurora was and is a great urban-legend manifested in the demise of the SR-71, mock-ups of some of the FDL lifting bodies and the emergence of early stealth technology. Closest we've ever got to Aurora is the X-43 and X-51. My opinion the Aurora concept has morphed into Blackswift which even today only exist in the CGI world. China will probably fly an Aurora knock-off before the US gets around to it.
The Aurora legend certainly took on a life of it's own.
By the mid-90s Aurora was supposedly an operational cryogenically fueled hypersonic reconnaissance aircraft meant to replace the SR-71.
Even a very small number of such aircraft would leave a huge logistical footprint, and that never materialized. The strategic reconnaissance mission of the SR-71 had long been orphaned, and other than for a few specific needs the tide was turning in favor of persistent surveillance rather than quick reaction.
That said, there is still considerable anecdotal information that suggests a small test force of very fast and/or unusually propelled aircraft were being flown at the time. There was also a role for such an aircraft in SAC's planning at the time, supporting the B-2 in prosecuting strategic relocatable targets (i.e. locating mobile ICBMs and telling B-2s where the haystack is).
It's a fascinating set of mysteries.
Yes there are still loose ends.
I guess you could call them UnFunded Opportunities!
Well.
Top Gun: Maverick.
