737 excessive rotation speed - a hard act to follow
 

Recently, an incident came to light involving an Indonesian registered Boeing 737 that would astonish Pprune readers used to hairy events common to that part of the aviation world. Edited for brevity. The take off run started on a 10,000 ft length runway.

The crew were apparently unaware of a problem with the captain's ASI until the 80 knot call by the first officer who was PM. The captain elected to keep going. The F/O called V1 and VR from his own ASI which was working normally. The captain continued the take off roll despite his own ASI giving a significant erroneous reading.

Approaching the end of the 10,000 ft runway the captain's ASI read 80 knots and the captain was forced to rotate to avoid an over-run. The aircraft then flew normally. Investigation revealed the actual ground speed at rotation was 298 knots, exceeding the maximum tyre speed limitation by close to 100 knots. A hard act to follow.

Groundspeed
 

298 Knots!!!! Must be a world record for a 737 take off.

I imagine that the aircraft would have required an extensive inspection of both landing gear assemblies (if the incident was indeed reported at the end of the flight!!). Did they return to base or continue on to original destination?

Are there any other dangers associated with exceeding maximum tyre speed other than burst tyres & landing gear issues?

737 excessive rotation speed - a hard act to follow
 

Geez... I'm really surprised that they did not burst all their tyres!

You can't beat having a few extra knots for the wife and kids....

Why didn't he loop it?

:p
Thanks BOAC.
Maybe the Captain had been reading up on 'improved climb' ?

At least climb performance with an engine out was going to be adequate!!

In some Asian cultures - and others - there is no way an F/O would ever take over from the captain who is regarded as a Deity. We have various acronyms to describe flight safety issues. CRM/TEM/CFIT for example. The latest is LOF or Loss of Face:D

Flap overspeed by at least 50 knots. Quite impressive safety margins...

No warnings on the 737 for exceeding max tyre speed?

Or disabled because of ASI disagree?

Do you actually believe this?

I would wait until there is at least something more factual to back this up.

I'd believe anything after some clown in SE Asia tried to get a 737 to land at a ridiculous speed ( may have been 200kts) about half way down the runway a few years back. The f/o was squawking a bit but didn't actually intervene. This seems mild by comparison.

737 excessive rotation speed - a hard act to follow
 

At what speed will the thing finally give in and start flying anyway?!! Short of having the stick pushed forward!

No warning, although it's quite easy to do it during Improved Climb and hot & high operations...

That was my first thought, too.

Frankly, the whole thing sounds apochryphal. But if any can provide a link to the investigation report of what would surely have been classified as a serious incident, I'll stand corrected.

See,if it were airbus,the stick would have gone up by itself:p
Case of an incapable pilot(s) or pilot incapacitation?

It is probably the World land speed record for a tricycle............

It certainly breaks Gary and George's record in the T5 Lighting at Coltishall all those years back.:)

737 excessive rotation speed - a hard act to follow
 

298 knots on the runway? I'd have to see the report. Sounds unlikely.

MH - remember this is PPrune.........you get what you pay for here

And nobody is suggesting, that the human sensors in the cockpit should have noticed that those big markers on the side of the runway were passing along quite rapidly on this takeoff?

Back to highschool
 

Just do some arithmatic with your highschool knowledge.

S = Vo * t + 0.5 * a * t2 (that is t squared)

Normally a lightly loaded airliner needs about 30 seconds to accelerate to about 150 kts (I know, that performance is already on the optimistic side).
Assuming a constant acceleration for the rest of the run, it would need 60 seconds to accelerate to 300 kts (close enough to 298).

Runway length needed to reach 300 kts under those assumptions - 4.500 metres (about 15.000 feet).

Conversely, if you want to have 300 kts within 10.000 feet of runway, the acceleration must be 7.5 kts per second. That would be an awful acceleration for an airliner - it would have to be empty and then also would require full thrust (not any assumed temp thrust reduction).

Like many others, curious to see the factual report.

Guy must have been pushing like hell to stop it auto-rotating. I didn't know Boeing made wheelbarrows.

Surely assuming normal T/O trim being set, the thing would have flown off itself long before 298kts......unless as mentioned he was actually pushing the column.

I'm not so sure either.

I guess the 98kt tailwind also played its part? :hmm:. What was that??? Did anyone hear a quack?

A 737-800 at flaps 1 has a liftoff attitude of 8.5 degs at normal speed for comparison.

Even assuming the 298 kts are true, the thing will not "fly off" by itself with 0 deg pitch. It's not a C172. The wing needs to be rotated into the airstream to generate sufficient lift.

I wonder if this is just miss reporting and the speed was 198 not 298 ?

As for continuing the takeoff with an airspeed disagree, considering the registry of the airliner in question, I find that totally believable :rolleyes:

Indeed. You wouldn't want to take off in an -800 with Flap 1 though would you? Normal for -700 but never had the laptop offer it in the -800 yet...

BS!!!

HOW could a 737 accel to 298 KIAS without getting airborne, with gear down and flaps in a Takeoff position?!?

HOW could a 737 trimmed for normal takeoff stay on the runway to 288 KIAS?

198? Maybe.

208? Maybe.

298? NO WAY!!!

Flaps 1 is a normal take off setting for the 800. 90% of my takeoffs on the 800 are flaps 1. Sounds like your company is restricting flaps 1 takeoffs.

298 kph maybe? That's about 160 knots.

A similar event
http://youtu.be/21qZPaCRSQI

As for continuing the takeoff with an airspeed disagree, considering the registry of the airliner in question, I find that totally believable

BerganAir did, and look what happened.

Each to their own, depending on runway length I would continue...

Look what happened to AirBerlin when they tried to stop in Dortmund. After that incident (and AF447), my airline increased training in flight with unreliable airspeed. Not a big deal to take it in the air and deal with it, as long as you know basic pitch and thrust values.

So it's actually possible to get to 298kts on the ground in a 737-800 in take off config without any forward control column input?

Just to prove how lunar this thread has become...What speed does oops! did the shuttle touchdown at?

Final approach (starting at 7nm and 10,000ft) 290kts, reducing in the pre-flare/flare to 195-205kts at touchdown.

It really came down like a brick...they would typically aim to be in the overhead of the landing strip at 50,000 ft and fly a kind of circuit to a 10,000 7nm final.....about an 18 degree glide slope on final!

As no-one yet has cited any authoritative source for the story, it probably will sit better in Rumours and News until it acquires some basis for fact ...

After 80 kts. You continue the take-off run for an airspeed disagree on B737.
Remember that after 80'kts. You should be "GO-minded".

If reall all asi's are incorrect, you still have pitch and thrust values, basic stick and rudder.

I assume it was at Jakarta and therefore on a typical 30+ deg C day? with density altitude already way past 3,000ft?

Well, this is about as scientific as you're going to get but according to MSFS and using the very respected PMDG 738 model, I reached the end of the runway at 215 kts (medium loads and fuel). Therefore I'd say someone misread the interim "report" and needs to go to Spec Savers (you're as blind as a bandicoot in Aussie speak).

The airspeed disagree was at the 80 kt call so isn't the Boeing SOP to reject at this point ?