.74 is a mach reference.
The cruise speed in an Airbus is generated by a computer based on a 'cost index' number. These numbers can range from 0 to into the hundreds [I seem to remember entering 999 at some point, but I'd never admit to it!]. The cost index number is supposed to balance fuel economy with other non-fuel costs associated with the flight… crew costs, engine per hour costs, misconnected passengers, headwinds or tailwinds, etc. Near as I can tell, most Airbus operators use cost indexes of somewhere in the teens up to around 75. Frontier consistently uses a cost index of 4… which can lead to some very low cruise airspeeds.
I would guess that most operators fly their A320 series aircraft at somewhere around .78 mach. Frontier is usually .76 +/- .01 unless we're at lower altitudes for whatever reason and then it gets stupid slow. Hence the reference to being passed by birds in flight or by an A380.
No longer accepting new Trust clients. Pretty much out of the law business completely.
A couple weeks ago, did some plane spotting from my balcony while waiting for a few AH-64s to come back (they didn't)
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Last edited by Ridge; 08-14-2014 at 21:46.
Nice pics, that Sea Fury is a treat to see.
I wanna see it up close! When we first moved here, I'd see it tearing across the sky and I swore it was a P-47. I called every airport I could find trying to find out where that P-47 was hangared and they all thought I was nuts. 'Twas several years before I found out what it really was. But man, that sumbitch sure scoots along, and it sounds like it's just loafing. I'd love to see it wide open!
There's a lot more of us ugly mf'ers out here than there are of you pretty people!
- Frank Zappa
Scrotum Diem - bag the day!
It's all shits and giggles until someone giggles and shits.....
This is from a while back, on one of W's last visits here (Buckley)
Not a plane but my son's ride at his deployment ceremony in December (he's a SSG, Flight Medic), should be home in just a few short weeks woohoo!!
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Last edited by Doc45; 08-16-2014 at 22:40.
There's a lot more of us ugly mf'ers out here than there are of you pretty people!
- Frank Zappa
Scrotum Diem - bag the day!
It's all shits and giggles until someone giggles and shits.....