-
Please take a moment and update your account profile. If you have an updated account profile with basic information on why you are on Air Warriors it will help other people respond to your posts. How do you update your profile you ask?
Go here:
Edit Account Details and Profile
Another "praise the Raptor" article
- Thread starter Lonestar155
- Start date
Actually you can tell the mach number from a photograph. It's impossible to be precise but it's possible to get an estimate based off of the shock wave angle. According to my math the raptor's going at least M1.15, or at least parts of it are. It's probably going faster than that but that's the best guess I can give.
I didn't know they had P-3 squadrons in Lemoore.
I suspect all the parts are moving at the same velocity, it's the air that is being moved at different velocities due to aerodynamic surfaces of the Raptor.
CWJones411
IRR
But what if the raptor is on a treadmill?
You can tell the Mach number by measuring the shock angle off a schlieren photograph, or any other photograph where you can actually see the shock. With the background there you can't see anything. If you're measuring the shock off of any point other than the nose, then it's a local Mach number along the body. In that photo, you can't see what you need to see. Now, take the photo of the low pass from the Blues' show in SF last year, and you can definitely estimate the local Mach number along a few points.
But even if you could measure the angle of a Mach wave at the nose, you'd have to know the angle of the nosecone, and then compare that to the wave angle. Did you take in to account that the nosecone angle of that aircraft varies? That'd be a tough calculation, and it makes a big difference if you used the 2-D angle vs the 3-D angle. Did you take in to account the aspect of the photo? Without that, it'd be hard to be even remotely close. My point is... transonic flow is tough, and Hacker's probably right. For me, I just compared figure 3 on this page (from the same article I referenced before) to the photo. The normal shock at the trailing edge that you can see in the photo is at around the same place as the M=.95 example.
But I am no expert, so as LeVar Burton would say, "But don't take my word for it!"*
* I really thought I'd go a whole reply without any quotes...
Nerds.
To continue with the nerd theme in this thread...
Technically the speed of sound is based upon temperature. Given that mach is a ratio of the speed of the aircraft to the speed of sound, different parts of the aircraft could have different mach numbers. Granted they'd be a small difference.
/end nerd stuff
I'm just playing. I know what you were pointing out, I'm just having fun with all this nerd speak. And Beans is right about the right photograph and all that other stuff. My aero brain is limited as I was more on the astro side of the aerospace stuff.
But it's the temperature of the air, not the aircraft, yes? Someone wearing coke-bottle glasses (and who has never seen a woman's genitals) please back me up here.
Brett
But it's the temperature of the air, not the aircraft, yes? Someone wearing coke-bottle glasses (and who has never seen a woman's genitals) please back me up here.
Brett
Well, you just ruled me out. Guess there's always wikipedia, right?
This thread just proves that if you studied too much in primary you got jets...
The rest of us who ended up as prop weenies or rotorheads were too busy sleeping with women to learn all this nonsense.
Smiles in full effect.
The rest of us who ended up as prop weenies or rotorheads were too busy sleeping with women to learn all this nonsense.
Smiles in full effect.
Beans flies helos....and studies alot. Nice new wings he's got though.
Interesting to note that the cone is not a 360 degree cone. My guess is he's transonic or right about the M 1.0 ish. There are 3 shock waves on the aircraft and the largest cone doesn't obscure the bottom of the jet. Also, the wingtips are creating visible vortices, likely due to some wing loading.
My guess is about a .96 IMN flyby with a pull to the vertical accelerated the air on the top surface and generated the cone.
Nice shootin'
My guess is about a .96 IMN flyby with a pull to the vertical accelerated the air on the top surface and generated the cone.
Nice shootin'