United_Fan From United States of America, joined Nov 2000, 7687 posts, RR: 6 Posted (13 years 7 months 1 week 5 days 7 hours ago) and read 2879 times:
I noticed on my last trip that ATC classifies Mexicana 757's as heavies. Is it because they operate to hot & high airports? Also , some Southwest 737's have alternating landing lites. Are they the only ones ? I thought I was seeing things?
Champagne For My Real Friends,and Real Pain For My Sham Friends
Cdfmxtech From United States of America, joined Jul 2000, 1341 posts, RR: 24
Reply 1, posted (13 years 7 months 1 week 5 days 6 hours ago) and read 2830 times:
Ohh know not this question again (Check this link to see how long this argument lasted - http://airliners.net/discussions/tech_ops/read.main/11570/)
The B757 is classified as a heavy for ATC separation for wake turbulence purposes. Some people are confusing this term used for ATC separation purposes as the definition of a heavy aircraft.
Below is an excerpt from a breakdown of an ICAO International flightplan:
Item 9: Aircraft type and wake turbulence category/number
Wake turbulence category— Indicate wake turbulence intensity created by
the aircraft :
H — Heavy (aircraft with a maximum certificated takeoff weight of
136,000 kg/300,000 lb or more).
M — Medium (aircraft with a maximum certificated takeoff weight of
less than 136,000 kg/300,000 lb, but more than 7,000 kg/15,500 lb).
L—Light (aircraft with a maximum certificated takeoff weight of 7,000
kg/15,500 lb or less).
The B757 is has a *MTOW of 255,000 lbs, so obviously it falls short of being a heavy. But because of the wake turbulence that it creates (or so they say), the B757 CAN BE CONSIDERED the equivalent to a heavy at times.
B747skipper From , joined Dec 1969, posts, RR:
Reply 6, posted (13 years 7 months 1 week 4 days 22 hours ago) and read 2595 times:
United Fan -
In the United States (US only) aircraft 300,000 lbs and the 757 are required to add "HEAVY" at the end of their call sign (flight number) when in contact with approach control, departure control and control towers - that is when they are in airspace of mixed sizes of traffic...
If you were hearing your xxx flight not called HEAVY, is because they were talking to enroute frequencies, which is not, approach, tower or deparure... Further, if you are overseas - HEAVY is not used...
Flashing lights is an option that any planes can get...