Todos
← Back to Squawk list
Official: Rivera plane plummeted almost straight
Mexico's top transportation official says a plane carrying Mexican-American music superstar Jenni Rivera plunged almost vertically from more than 28,000 feet and hit the ground in a nose-dive at more than 600 miles an hour. (www.chron.com) Más...Sort type: [Top] [Newest]
This one kinda sounds like an MMo excursion, except at 28000 they were still in the indicated airspeed, mach transition point. Depends on OAT. Anywho, it is very easy to exceed VMo, MMo at 280 in a 20 series Lear and when you do you get what is called mach tuck. The nose goes down no matter what because the center of lift moves aft and only gets worse because the nose is going down and the airspeed is increasing. Unfortunately, the inexperienced guy will now deploy the spoilers, which drives the nose down some more. Oops. By now you are probably at .86 or .88 mach and the ailerons start to snatch or at least buzz. Depends on who painted them and if they were balanced properly. Some more oops because MMo is .82 and not a flexible # in a Lear. In the sim the proper recovery was throttles to idle, gear down, screw the gear doors, and slowly pitch up to recover from the overspeed. Not to be glib, but sometimes the instinctive approach is not the correct one. I still suspect that this airplane was not RVSM legal. Nobody flies these airplanes at 280 because they burn too much fuel down there. These airplanes are at home at 450 with a good set of engines. Fuel burn gets back to about 10% of the gross weight or 1200 to 1300 lbs. per hour. About the same as Garretts at those altitudes, if you can get em there.
For the uninitiated among us, what is an "MMo excursion?" And also, "RSVM?"
Mach/Velocity Max Operating or the Maximum Operating Limit Speed
Ray, FAR part 1 abbreviations and definitions. Don't know what page. Not being a S.A. just sayin, their published and you'll also find Vx, Vy, Vne and all those other things you learned for your private. Jose is correct, my theory is an overspeed, with no associated stick puller, overspeed warning. It's all over pretty quick on a dark night in a worst case scenario. Right or wrong, gonna be pretty tough to prove conclusively with what's left. Google RVSM and read about it on Wiki. Probably won't affect you but good to know.
28,000 may have been where it had its initial issues, maybe in climb or descent. I'm not sure if the 28,000 was the final altitude and can't find it anywhere that it was or wasn't. Also, if only flying for 100 miles, I don't know that the pilot would bother getting to the higher FLs. However, not having any time in a Learjet, I can't say anything for sure, but it does sound confusing (possibly confounding for those without a lot of time) when MACH TUCK is reached. I'm hopeful for a full report, but if it nosed in at 600+MPH straight down, even if a Black Box was installed, I doubt it would survive with any useful information. I'm not sure that anything will be left of much value from a catastrophic crash like that!
Starwood Management of Las Vegas, had their other airplane confiscated by the DEA in McAllen Tx.......interesting...............