Bruce From United States of America, joined May 1999, 5089 posts, RR: 14 Posted (11 years 10 months 3 weeks 4 days 11 hours ago) and read 5342 times:
Question is: Can a heavy jet, like a Dc10 or 747, safely take off from a runway of only 6,500 feet? Assume that the plane is empty and not even carrying a full load of fuel either, like a ferry flight. My guess is that it wouldn't be possible.
Bruce Leibowitz - Jackson, MS (KJAN) - Canon 50D/100-400L IS lens
411A From United States of America, joined Nov 2001, 1826 posts, RR: 8
Reply 1, posted (11 years 10 months 3 weeks 4 days 10 hours ago) and read 5292 times:
A few years ago, delivered a Lockheed TriStar to a rather short runway...5000 feet, for maintenance, then out again, for a short ferry flight to operational base.
No problem whatsoever.
Shorter runways require larger flap settings (for runway length) at the expense of second segment climb performance...usually not a problem.
OTOH, have rolled 11,500 feet on a 12,000 foot runway before Vr, and the weeds go by rather quickly...this was with B707 equipment with P&W JT4A engines.
Gives a new meaning to up close & personal with the far end of the runway.
Flyf15 From , joined Dec 1969, posts, RR:
Reply 2, posted (11 years 10 months 3 weeks 4 days 10 hours ago) and read 5278 times:
Per Boeing's performance charts, the 747-400 on a standard day at sea level with zero wind can takeoff from a 6500ft dry runway at up to around 700,000lbs takeoff weight (varying slightly due to engine choice). This is enough for max payload and fuel for a 3000nm flight. Under the same conditions, it is capable of landing at up to the max landing weight.
Per MDC's performance charts, the DC-10-30 on a standard day at seal level with zero wind can takeoff from a 6500ft dry runway at up to around 460,000lbs takeoff weight (varying slightly due to engine choice). Not sure what the resulting range would be for max payload at this weight. Under the same conditions, it is capable of landing at up to the max landing weight.
B747Skipper From , joined Dec 1969, posts, RR:
Reply 3, posted (11 years 10 months 3 weeks 4 days 2 hours ago) and read 5196 times:
Dear Bruce -
Runway required and performance for takeoff (and landing) for large airplanes has been explained in details by our friends here above, with some numbers.
Regarding "how long a runway" is needed depends on many factors of weight of the aircraft (heavy or light) - is it at sea level on a cold day and a good headwind, which is the best, or is it at a high elevation like Denver, with a hot temperature of an early afternoon, no wind... many factors enter in the equation. we have charts which permits to compute the runway required, for takeoff or landing...
Further thing to remember, is that airplane "X" may require say a 10,000 feet long runway for takeoff, but that is including safety factors such as loss of an engine at speed V1, and to abort (stop) the aircraft on that runway...
So if we say we need "10,000 feet" to get that baby in the air, in practice, if you watch the takeoff, we might be leaving the ground much earlier than that, maybe only rolling some 7,000 feet... the 3,000 feet extra is just there in case things turned bad, during our takeoff with one of our engines failed.
For landing as an example, we know that we legally must be able to stop the airplane on 60% of the effective runway length... that is if the runway is 5,000 feet long, that airplane can stop on a 3,000 feet distance (with NO REVERSERS accounted for)... Then we have "wet runway" correction factors.
All that is the subject of aircraft performance... FAR/JAR 25... where you would read mention of wordings like "takeoff distance", "clearway", "stopway", "obstacle clearance", "takeoff climb" or "landing climb" segments... any many more to confuse you and me...
B747Skipper From , joined Dec 1969, posts, RR:
Reply 5, posted (11 years 10 months 3 weeks 4 days ago) and read 5163 times:
Even though I "know" the "wheels" will only roll on the runway concrete for some 7,000 feet, if my runway analysis says I need 10,000 feet for that takeoff, I HAVE TO HAVE 10,000 FEET...
I know what you say and you mean... but can you tell me one engine WILL NOT FAIL...?
In the airlines we cannot take the chances...
In the military, it was different. In some cases, they forgot these factors.
When I flew the KC-135 in my younger days, we were 302,000 lbs gross weight, with thousands of gallons of JP-4 on board... and there was no account for stopway and clearway... just a table, GO, and start you stopwatch for the roll, and pray God your J-57 engines were healthy and water injection worked.
Happy contrails -
KYIPpilot From United States of America, joined Oct 2003, 1383 posts, RR: 6
Reply 6, posted (11 years 10 months 3 weeks 1 day 23 hours ago) and read 4961 times:
Kalitta 747's operate out of KYIP (Willow Run) all the time, and the longest runway is 7,500 ft. They take off with less fuel and make a fuel stop at an airport on the way that that can handle a fully fueled and cargoed 747. We also see some DC-10's once in a while.
"It starts when you're always afraid; You step out of line, the man come and take you away" -Buffalo Springfield
Rick767 From United Kingdom, joined Jan 2000, 2662 posts, RR: 50
Reply 8, posted (11 years 10 months 2 weeks 5 days 21 hours ago) and read 4767 times:
Remember it also depends on engine thrust. I used to fly 763s non-stop from BHX to CUN (loaded up with 315 sun-seekers) and we could get off that 8,500ft runway about 10,000kg less than MTOW no serious problem.
American Airlines though would often have a problem with their 763 if they got a good load on the BHX-ORD flight managing a non-stop service and I always wondered why (BHX-ORD being about 3,400nm with BHX-CUN being over 4,200nm)....
I discovered the reason was that AA had the CF6-80C2B6 on their 763s while we had the CF6-80C2B7F. The difference is that we had an extra 2,100lbs thrust to play with (62,100lbs compared with their 60,000lbs). And we did need that extra 2,100 I can assure you.
So at the same TOW, we could achieve a shorter t/o roll than that AA 763.
I used to love the smell of Jet-A in the morning...