747luvr
Posts: 331
Joined: Thu Jul 21, 2005 1:39 am

Long Take Off Rolls

Wed Aug 03, 2005 1:00 am

Does anyone know of some very long take off rolls? I have been on a few 45-50 second rolls, but nothing quite a minute? Anyone wish to elabororate about a long take off?
 
philb
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RE: Long Take Off Rolls

Wed Aug 03, 2005 1:41 am

Take off is an exact science. Each take off is based on calculations which include the total aircraft weight, the runway slope and adhesion, the wind component, the height above sea level, the temperature and the pressure.
The power setting needed is then calculated along with the V1, V2 and rotate speeds and the distance needed to achieve these. Mmost jet aircraft take off on 75% - 80% power wherever possible to maximise time between major engine overhauls and to save fuel.

In hot conditions, at high airports and/or when an aircraft is operating at maximum weight for the runway, the time to rotation can be comparatively long.

Mexico City is renowned for long take offs. In the 1960s and 1970s some of Mexicana B727s had JATO (Jet Assisted Take Off) bottles to assist the engines and these were regularly used.

Even low and cold runways can see long take offs. I was on a BA 747-200 ex LHR for Miami in March 1988. The wind component changed, we returned to the gate, off loaded some freight and even then only rotated at 57 seconds which, on 28R at LHR (as it was then) takes you a long way down towards the reservoirs!
 
goldenargosy
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RE: Long Take Off Rolls

Wed Aug 03, 2005 1:42 am

I don't know what it was in seconds or minutes, but last February I was on Singapore's 340-500 taking off from Newark bound for Singapore. At a certain point my heart started racing because I thought the thing would never leave the ground. Seriously, there must have been a foot or two left of the runway before it became airborne. That was by far the longest and most worrisome roll I'd ever experienced.
 
1MillionFlyer
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RE: Long Take Off Rolls

Wed Aug 03, 2005 1:44 am

DEN in the summer is always interesting, you don;t build a 16.000 ft runway if you don;t need it !

I saw the LH 744 taking off the other day...what a site to see that heavy bird trying to climb out in 38C/96 F heat  Smile
Golf Foxtrot you are cleared for departure
 
FlyGuyClt
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RE: Long Take Off Rolls

Wed Aug 03, 2005 1:49 am

Anyone ever been on a full DC9-50 in July zooming down the runway in MIA going on a 3 hour flight? The roll is almost as long  Smile

Safe Flying ~!
Florida Express, Braniff II and ......
 
Udo
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RE: Long Take Off Rolls

Wed Aug 03, 2005 1:57 am

I once had the pleasure to take off in a fully loaded Iberia A340-300 from Madrid on a hot evening (bound for Miami). Don't know how long it lasted in seconds, but after a while I thought we would be driving to Barcelona rather than getting airborne...  scratchchin 


Regards
Udo
Me & You & a Plane Named Blue...
 
hrhf1
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RE: Long Take Off Rolls

Wed Aug 03, 2005 2:14 am

A fully loaded AC 762 from Las Vegas in July certainly took some time to rotate the day I was on it. Temperature was about 114F, (45C) and at 2200' it made for a loooooong roll. No exact time, but I'd guess it was 50 seconds minimum....hence 14500' of runway. Add to that the convection heat bouncing the aircraft around right after takeoff and you had some antsy pax! It was good fun!

[Edited 2005-08-02 19:22:29]

[Edited 2005-08-02 19:23:13]
 
cartoonranger
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RE: Long Take Off Rolls

Wed Aug 03, 2005 2:19 am

The RAF still go off in Bahrain with VC-10's at 152 tonnes +45 degrees C Outside Air Temp. The take off roll is truly monumental. Of course performance dictates that losing a donk above V1 should not be a problem, but having glared the runway end lights squarely in the face on more than one occasion i always prayed that it wouldn't happen as i severly doubt she'd want to fly.
 
SA7700
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RE: Long Take Off Rolls

Wed Aug 03, 2005 2:38 am

Fully loaded flights in JNB can take up a huge chunk of the runway. I have heard that QF sometimes delay their departures (SDT18h00) out of JNB in order for the temps to come down and the payload restrictions to be lowered.


Rgds

SA7700
When you are doing stuff that nobody has done before, there is no manual – Kevin McCloud (Grand Designs)
 
ACDC8
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RE: Long Take Off Rolls

Wed Aug 03, 2005 2:50 am

The longest take-off roll I've ever experienced was in 1991. We were taking off from YYC's RWY 34, which is 12,675 feet, on one of KLM's 747 combi's. Anyway, we were sitting at the end of the runway, brakes on, full power, sat there for a few seconds, brakes off, and off we went. We were just rolling and rolling for what seemed like the longest time, by the time we finally got in the air, we were just crossing the other end of the runway!

I think one of the reasons we needed such a long take-off roll was due to the fact that they stuck a helicopter (minus the rotors) in the back of the airplane! So we must have been pretty well maxed out with weight!
A Grumpy German Is A Sauerkraut
 
dkny
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RE: Long Take Off Rolls

Wed Aug 03, 2005 2:58 am

Most long haul take off rolls out of ADD are long. ADD's high alt is the reason for the long take off rolls.
 
goingboeing
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RE: Long Take Off Rolls

Wed Aug 03, 2005 3:01 am

I don't know how long the roll was, but I was on a Piedmont flight from CLT-DFW back in the mid 80's. My coworker (who also travelled a lot) was sitting next to me and the engines spooled up and we started to roll. And roll. And roll. And roll. Finally she looked at me with a panicked look on her face and said "Shouldn't we be in the air by now?" I said "yes" (although we were still rolling down the runway) when FINALLY the plane rotated and we took off. Scared the living sh*t out of me.
 
FLYiCRJ
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RE: Long Take Off Rolls

Wed Aug 03, 2005 3:03 am

Last July I was on Continental's flight 15 from EWR - HNL. If you are familar with Newark airport you will understand what i am talking about here. We taxied to 22R started our take off roll and we were past the Fedex building before we rotated. We weren't more than 50 feet off the ground before the end of the runway came up. Now my question is because of our long T/O roll, what happens if they had to perform a rejected takeoff?
 
AirRyan
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RE: Long Take Off Rolls

Wed Aug 03, 2005 3:10 am

Pilot's opt to derate the takeoff rolls to save wear and tear on the engine as well as gas. I'm sure it's not just a decision of the pilot as much as it is often company policy per the condition.

As part of the pre-flight on your FMC you have 3 choices - normal full power and then two derated options. The computer takes into account your load, fuel, ambient temp, and runway length to calculate just how much power is needed to takeoff on that runway at that time with that load. Pilot's also have the option to derate the climb by two gradients as well.
 
goingboeing
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RE: Long Take Off Rolls

Wed Aug 03, 2005 3:11 am

Quoting FLYiCRJ (Reply 12):
Now my question is because of our long T/O roll, what happens if they had to perform a rejected takeoff?

As far as I know, once a plane passes V1, there isn't any rejecting a takeoff.
 
cartoonranger
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RE: Long Take Off Rolls

Wed Aug 03, 2005 3:30 am

Sometimes aircraft will deliberately spend longer on the runway anyway. If there is a large obstacle at the end of a runway, it is often safer to leave V1 as late as possible. This is because, should you lose an engine you would be better off on the ground rather than trying to fly over it. For the VC-10 This is factored in Regulated Take off graphs which dictate what speed V1 will occur. It may be hard to believe but even heavy at 150 knots, most modern day aircraft have phenomenal stopping power so the actual stopping distance may not be as great as you think!

Runways can also have different Take Off Distance Available (TODA) and Accelerate Stop Distance Available (ASDA - i.e. 0 Kts to V1 and back to 0 Kts again)
 
BritPilot777
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RE: Long Take Off Rolls

Wed Aug 03, 2005 3:32 am

You see it even at LHR quite often, a lot of aircraft take up nearly all the runway, amazing sight seeing them lift off though at the end with some awesome wing flex!
Forever Flight
 
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United_fan
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RE: Long Take Off Rolls

Wed Aug 03, 2005 4:09 am

Champion 727's in LAS sure have long rolls!
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FlySSC
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RE: Long Take Off Rolls

Wed Aug 03, 2005 4:30 am

The following was loooong take off run... :


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Photo © Sam Chui

 
jeffry747
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RE: Long Take Off Rolls

Wed Aug 03, 2005 8:44 am

A while back I was in the UPS parking lot at SDF, which is situated at the departure end of 17L (8500ft). Had a full 741 going to ANC rotate with less than 1,000 ft left. This puppy cleared the blast fence by about 20-30 ft and thundered over my head low enough that I could almost count the lug nuts on the main landing gear, which were just starting to retract. Best takeoff I have ever seen.
C'mon Big B, FLY!
 
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ATA L1011
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RE: Long Take Off Rolls

Wed Aug 03, 2005 9:03 am

Back in 97 on N195AT, L1011-1 from LAX to HNL that thing was loaded with over 300 people and the take off roll was 55 seconds, I remember us rotating just past the Tom Bradley Terminal on the South Side of LAX.
Treat others as you expect to be treated!
 
vulindlela744
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RE: Long Take Off Rolls

Wed Aug 03, 2005 9:47 am

I flew from Miami to Cape Town back in '97. It was a non stop on a fully loaded 747-400 and it took almost the whole south runway to get airborne. That runway is almost 13,000 ft. It was really something.
 
N270FT
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RE: Long Take Off Rolls

Wed Aug 03, 2005 9:52 am

In 1998, I was on A Virgin 747-200 "California Girl" From MCO-MAN. I seriously thought the plane would never leave thr ground.

Also, in 2000 I was on this same plane from LGW-EWR and they had to turn the cabin electricity off over Newfoundland because there was smoke in the cabin. The plane landed safely however, and I cringed everytime I saw that plane since.
 
jmc1975
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RE: Long Take Off Rolls

Wed Aug 03, 2005 10:02 am

My longest takeoff roll: I flew from Atlanta to Cape Town nonstop in Jan. 2003 on an SA 744 (ZS-SAY). Although the outside temp. was at the freezing mark, the flight was restricted by 20 pax. About 45 seconds into our takeoff roll, the pax began to say things like "get up" and were in doubt if we would make it. I had an aisle seat on the side of the aircraft, which had a perfect view of the left winglet. As we began to rotate, I saw that winglet shoot up about 10 feet. As we lifted up, there was condsierable airframe shudder and we had a slow climbout as we barely clear the Georgia woods by the Chick-fil-a headquarters.
.......
 
jyatlantic
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RE: Long Take Off Rolls

Wed Aug 03, 2005 12:00 pm

I was on a BA 744 out of JNB at full capacity. The roll was expectantly long with the full load and altitude.
 
YBCS
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RE: Long Take Off Rolls

Wed Aug 03, 2005 5:05 pm

I can remember a flight on a 707-338 of Air Nuigini from HNL to POM in 1981 where thundering down the Reef Runway I saw the 1000 foot remaining panel flash by the window and we still hadn't rotated. I vaguely remember saying a quick prayer, we had to have used every bit of concrete available. Must have been really heavy.

When as a flight engineer on C-141s in the 80s I can remember taking off from Clark AB in the Philippines during the middle of the afternoon at max gross weight. We hit 100 KIAS and the airspeed tape stopped moving for what seemed like an eternity, as we continued to eat up runway it became obvious there was insufficient pavement to stop. The pilot made the statement we were commited and we continued, the tape finally started moving again and we just cleared the concrete wall at the south end of the field. After we started breathing again and pulled our shorts out we notified tower we had experienced possible wind shear. They came back confiming wind direction had just changed almost 180 degrees. That was fun....NOT!
"All that is necessary for evil to succeed is that good men do nothing" - Edmund Burke
 
Matt27
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RE: Long Take Off Rolls

Wed Aug 03, 2005 6:15 pm

I flew SAS A340-300 CPH-BKK-CPH, and the roll at CPH was 55 sec, and at BKK was 65 sec. The A340 wasn't very powerful during take-off, but a long roll is always nice. The most powerful take-off ever: PG B717 at Koh Samui.

//Mattias
Man ska inte dricka rödvin i en vit hall.
 
ZK-NBT
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RE: Long Take Off Rolls

Wed Aug 03, 2005 6:34 pm

My first ever flight AKL-HNL on a CO 742 had rather long take off rolls from both airports my dad tells me, I can't remember since I was only 4 at the time.
 
powerofpi
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RE: Long Take Off Rolls

Wed Aug 03, 2005 7:54 pm

 
planemad
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RE: Long Take Off Rolls

Wed Aug 03, 2005 8:07 pm

Go to JNB if you want long takeoffs. I have flown a CE 732 out of there which had a 1 minute roll and a VS A343 out of there which had a 1 minute 5 second roll!

Sam D.  Smile
 
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SQ773
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RE: Long Take Off Rolls

Wed Aug 03, 2005 8:43 pm

My first extra long take off was in DXB back in 1999 on board a fully loaded LH 343 . It was 02.00 am and the weather was very hot and humid . I remember thinking whether we would ever get airbone, and I have to recognise that after a "while " I began getting nervious...

On the ther side, the shortest wide body take off I have ever seen was in LHR. The RG Boeing 743 lifted off just after 5-10 seconds of rolling. ( can´t remember exactly ) I knew the flight was going to CPH, surely almost empty, but I was absolutely amazed, I have never seen it again, and I have seen thousands of take offs...
 
TIMC
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RE: Long Take Off Rolls

Wed Aug 03, 2005 9:39 pm

Sometimes at MAN, the PIA and EUK birds take up almost all of the runway to take off.

The EUK regularly has 450+ pax on it, so its one heavy plane!

Why is it though that the hotter it is, the longer the take off roll?
 
pilotaydin
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RE: Long Take Off Rolls

Wed Aug 03, 2005 9:47 pm

call me ULTRA nerd, back in high school i did a study for a year for my math project on the average take off time for an airliner, i collected data for MONTHS from various european airports, with my bicycle and my pen/pad. I found in the end the average take off roll in time for all my samples (over 1500) was 32.4 seconds lol, i know some people are going to post some interesting replies to this but hey...been there done that list is getting bigger  Wink

My longest roll personally as from ATL-FRA LH444 last year, 1 minute 8 seconds till rotation YES it was an A340.... long live the earth's curve
The only time there is too much fuel onboard, is when you're on fire!
 
jetstream63
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RE: Long Take Off Rolls

Wed Aug 03, 2005 9:53 pm

I was on board a Singapore Airlines 747-400 (9V-SMA) departing fully loaded for LHR in 1989 and I timed the take off roll at 59 seconds.
 
broke
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RE: Long Take Off Rolls

Wed Aug 03, 2005 10:12 pm

One of the more interesting take-offs I had experienced was on a 727-200 advanced with -17 engines. We coming out of La Paz and could only load about 100 pax; the plane's capacity was 149. I was jumpseating.
The runway is 13,000' long with a definite down slope in one direction. You land in either direction, but you always takeoff going down hill.
As we taxied out the tower called the winds at 8 knots with a full tailwind component.
I looked at the windsock at the end of the runway and we did have a tailwind, but the windsock was fully extended. At sea level that equates to 15-20 knots and not 8.
Taxi onto the end of the runway, set brakes, run the engines up to 80% N2, release brakes, and set takeoff power.
At about 3,000' down the runway the airspeed indicator had yet to indicate anything.
Slooowly it came off the peg. End of the runway was coming up quickly.
V1, Vr, V2, whoosh runway lights at the end of the runway went just underneath us.
Phew!!  wideeyed 
 
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ZSOFN
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RE: Long Take Off Rolls

Wed Aug 03, 2005 10:28 pm

Flying LHR-JNB on VS's 744 G-VFAB in late 2001. The roll on 27L took ages! We must've been full cos we cruised at FL290 until south of the Sahara!

On the opposite end of things, last week flew EZY's 73G G-EZJL from BRS to MAD and rotated on 27 in less than 3,400ft. Thought that was pretty impressive.
 
Logan22L
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RE: Long Take Off Rolls

Wed Aug 03, 2005 11:27 pm

Quoting Pilotaydin (Reply 32):
I found in the end the average take off roll in time for all my samples (over 1500) was 32.4 seconds

I always count in my head the time to rotation (which can be a bit subjective due to "turn-and-go's" and counting in my head, but as a musician, I have a pretty good metronome in my head). Lately, I've flown on 733, 738, DC-9-30, 752, 753 and A333. I've gotten figures that range from about 30-35 seconds, so it's good to see that your far more scientific measurements corroborate mine. Even the A333 was right in this range, more or less.

I'm wondering which aircraft you would have (or not have) included? Were many A340s in your measurements? How about 747s and, on the other hand, RJs? Were the data normally-distributed or log-normally distributed? Ha, you thought you were a nerd!
"The deeper you go, the higher you fly. The higher you fly, the deeper you go."
 
ikramerica
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RE: Long Take Off Rolls

Wed Aug 03, 2005 11:38 pm

I was on CO75 HAM-EWR yesterday, and seeing as how this pushes the limit of the 757, it was a longer roll than you normally get on a 757. We also did not have winglets, unlike the first few weeks of HAM service. Now I believe Berlin gets winglets every day, as it is even further than HAM.

Yesterday morning I spent some time spotting from the observation deck. All other flights (73X, A32X, F70, CRJ, AVRO) entered the take off runway at HAM at the "normal" entry points, but our CO752 taxied to before the runway officially started, to what looked like a helicopter circle and started our roll from there. The first few seconds were bouncy because we were on the 'pre-runway' area, then when we rolled onto the runway, it smoothed out.

It was not warm, but the flight was completely full. HAM has a long runway, but we seemed to use most of it. The 757, even fully loaded, doesn't need to use it all, but as others said, the pilots likely used it all for other reasons. We likely passed V1 long before we rotated, but they wanted to have good speed before lift off to quickly jump above the cloud layer around HAM. At least that's my guess.
Of all the things to worry about... the Wookie has no pants.
 
United737522
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RE: Long Take Off Rolls

Thu Aug 04, 2005 3:10 am

Quoting 1MillionFlyer (Reply 3):
DEN in the summer is always interesting, you don;t build a 16.000 ft runway if you don;t need it

On my last flight, we were on a 738 DEN-MIA and it was full. Takeoff was exactly 48 seconds and we used up a good portion of the 16000 foot runway.
'Michael Mooronism' ~Jetjack74
 
legacy135
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RE: Long Take Off Rolls

Thu Aug 04, 2005 3:28 am

Quoting Ikramerica (Reply 37):
We likely passed V1 long before we rotated, but they wanted to have good speed before lift off to quickly jump above the cloud layer around HAM. At least that's my guess.

Not really..... under as also overroation is having a negative influence on the actual performance. So the Vr is a given number for the circumstances you found them yesterday (weight, temperature, elevation etc.)
What the crew is going to do then with those numbers is the so called "balanced take off". This means, at V1 they will either stop in the runway or reach 35ft at it's end, flying the plane at V2 which is the best angle of climb at "today's numbers".
It is imperative to stick to those numbers, as only using them will assure the crew to make it.
If you are interested, I explained once on a similar topic, talking about flapless take offs, the physics of a take off, that answers the same aspects.
RE: Flapless Takeoff (by Legacy135 May 27 2005 in Civil Aviation)

I hope you enjoyed Germany  Wink Cheers and Rgds
Legacy135
 
Ken777
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RE: Long Take Off Rolls

Thu Aug 04, 2005 3:41 am

QF 744 SYD-LAX a few years ago. The pilot actually announced that the plane was heavy and we would take 60 seconds going down the runway. I timed it and he was spot on to the second. Now I time all 744 takeoffs and they are generally in the 45 - 55 second range. I'm starting to develop a theory that the roll time has a fairly good direct relationship to the revenues the airline are going to make on that flight.
 
jsnww81
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RE: Long Take Off Rolls

Thu Aug 04, 2005 6:08 am

I flew out of Mexico City on a domestic flight to Hermosillo back in May, and the takeoff roll was so long I didn't think we'd ever get off the ground. I shot a video of the takeoff, which is posted on Flightlevel350.com:

http://www.flightlevel350.com/viewer.php?id=2542
 
spacecadet
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RE: Long Take Off Rolls

Thu Aug 04, 2005 6:09 am

Couple years ago I flew from JFK-NRT in a 747-400, fully loaded with pax and fuel on a 97 degree F day. ANA has nosewheel cams on takeoff and man, my heart was going pretty good watching that thing. By the time our main wheels had left the pavement, the end of the runway was already out of view (under the camera) on the nosewheel cam. I wasn't even sure we'd clear the trees at the end of the runway. I have no idea how long in seconds the roll was but we used about every inch of that runway.

Coming back was similar (Japan's pretty tropical at that time of year) but not quite as close. They may have ramped up the power closer to 100% on the NRT-JFK takeoff roll.

I know takeoffs are an exact science but it sure didn't seem like they left much of a safety margin on the JFK takeoff.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
N766UA
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RE: Long Take Off Rolls

Thu Aug 04, 2005 6:27 am

You wanna talk about eating up runway try the 727. I've seen plenty of those buggers use every last foot of runway before becoming airborne and climbing like a dog. But, once they get up there, they can really move!
This Website Censors Me
 
luv2fly
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RE: Long Take Off Rolls

Thu Aug 04, 2005 6:43 am

I flew out of LAS on a hot, hot day flying on a L1011 that once we finally took off I thought for sure we had used the PHX airport at that point. LONG!
You can cut the irony with a knife
 
legacy135
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RE: Long Take Off Rolls

Thu Aug 04, 2005 7:03 am

Another reason for relatively long take off rolls is saving engines:

As you may imagine, gentle use of brakes and making use of the runways length to slow the plane down, the same counts on take off. If the engines are not brought to max power and the last pound of thrust is squeezed out, the engines live can be extended significantly.
In most modern planes we can choose between a "max take off" or a "flex take off". The "flex take off" is a power setting that gives that much power, that we have enough to make it with the runway available, including obstacles, ev. engine failure etc. We just fit our balanced field take off into the area we have and get as much power we need what in most cases is not the maximum.
Most operators run their engines on a contract with the manufacturer of those. They deal out fixed rates per engine hour for parts, spare engines etc. The less power they squeeze out of their engines, the lower the rates...
Many of today's engines do have maintenance intervals which are "on condition". The engine datas are downloaded periodically from the FADEC's (Fully Automated Digital Engine Control) and analyzed by the manufacturer. They will decide if an action is necessary. For sure, the more gentle they are handled, the longer they last...

Coming to the aircrafts performance limit, also a plane being quite sporty in "middle weights" starts to use space and will climb relatively shallow.

Combining max weights with hot temperatures, a flex take off power setting and you may find the explanation why sometimes even well powered aircrafts like a 757 or so start to feel at it's limits.
 
jeffry747
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RE: Long Take Off Rolls

Thu Aug 04, 2005 11:41 am

Quoting Jsnww81 (Reply 41):
I didn't think we'd ever get off the ground.

Judging by the runway markings, you rotated with less than 500 ft of runway left.
 Wow!

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C'mon Big B, FLY!