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View Full Version : Another Allegiant RTO


iskyfly
28th Aug 2015, 12:44
Incident: Allegiant B752 at Austin on Aug 24th 2015, rejected takeoff due to engine indication (http://avherald.com/h?article=48b73d05&opt=0)

striker26
28th Aug 2015, 12:58
A lot of incidents regarding safety these days for Allegiant, nothing wrong with having an old fleet if you take care of maintenance. Sucks that their operations are so slim, but i think their compromising safety, one airline i'd avoid.

Hotel Tango
28th Aug 2015, 14:20
Then again rejected take-offs due to "engine indications" (often erroneous) are ten to the dozen on a daily basis around the world. Of course, with their recent "troubles" Allegiant will now make headline news for any event that occurs to them specifically.

Airbubba
28th Aug 2015, 15:34
The aircraft pulled into the gate and was subsequently seen with 7 of 8 main tyres deflated.

And that was on a 12,000 foot runway in a '75. Those dang fuse plugs... ;)

Next time I'm sure they would pop off the autobrakes and let it roll to the end, most 757's don't have brake temps, and they only let you know how hot things are a few minutes later.

Must have been an engine failure or fire indication to do an RTO above 80 knots, right?

Did they have one fire loop deferred on a Rolls and then lose the other one when the power came up perhaps? Seems like you get a fire warning in this case.

Hope it wasn't loss of an EPR gauge or something like that. You keep on trucking above 80 knots, BTDT...

hans brinker
28th Aug 2015, 15:54
An Allegiant Boeing 757-200, registration N903NV performing flight G4-453 from Austin,TX to Las Vegas,NV (USA), was accelerating for takeoff from Austin's runway 17R when the crew rejected takeoff at high speed (about 110 knots over ground) reporting an engine (RB211) indication as reason for the rejected takeoff. The aircraft slowed safely and vacated the runway via taxiway T about 2100 meters/6900 feet down the runway.

And that was on a 12,000 foot runway in a '75. Those dang fuse plugs...

Next time I'm sure they would pop off the autobrakes and let it roll to the end, most 757's don't have brake temps, and they only let you know how hot things are a few minutes later.

Must have been an engine failure or fire indication to do an RTO above 80 knots, right?

Did they have one fire loop deferred on a Rolls and then lose the other one when the power came up perhaps? Seems like you get a fire warning in this case.

Hope it wasn't loss of an EPR gauge or something like that. You keep on trucking above 80 knots, BTDT...


Somewhat surprised they let the airplane slow down enough to take a taxiway halfway down a 12,000 ft runway apparently without consideration of brake temperature....

RatherBeFlying
28th Aug 2015, 16:29
I faintly recall an RTO accident / incident decades back where the report recommended full braking instead of gentle braking to the end of the runway which counterintuitively heated the brakes more because of rolling resistance.

Physics tells us that the energy from braking from a given speed will be the same, but rolling resistance adds to the total sum.

The next question is where you prefer to change the tires, hopefully on the same rims.

Airbubba
28th Aug 2015, 17:39
Physics tells us that the energy from braking from a given speed will be the same, but rolling resistance adds to the total sum.


Don't rightly know about all that physics stuff but I'd still pop off the brakes and roll to then end if I could. There are other initial priorities but I hope I would remember if there was a lot of runway in front of me in a smaller plane like a 757 or 737.

Heavy braking to make a turnoff sure heats up the wheels more than light braking to roll further down the runway in my experience.

The demo I often see lately in a Boeing widebody is to use the ever so popular autobrakes 2 setting for landing followed by stomping on the brakes to make the turnoff nearest the gate. It definitely seems to get the brake temps up from what I can see.

I'll confess that, thankfully, I don't have a lot of high speed RTO time anywhere but in the sim. Knock on wood...

On the takeoff roll, when RTO braking cuts in everything is happening fast, you gotta make sure the reversers are out and the speedbrake is up, you've clicked off the autothrottles so they don't come back up (not a problem at high speed but procedural) etc.

I prefer to turn off the autobrakes with the selector switch, some operators frown on that and want you to always use the brake pedals since the FO might not be able to reach the selector in a normal landing.

I think the old Boeing manuals said to come out of reverse and pop off the brakes when slowed to taxi speed. Now there is something like 'max reverse and braking until stopping on the runway is assured'.

No matter what you do, the feds will sit down with a stack of manuals and take hours to second guess everything you did in the space of a few seconds.

The next question is where you prefer to change the tires, hopefully on the same rims.

Also, hopefully the crew checked the RTO brake energy tables to see if they were in the dark area where the fuse plugs might melt.

I've seen someone else have the brakes lock up on landing due to an antiskid fault, blow all the tires and smoke the brakes on the runway. New tires put on to tow off the runway, then new wheels and brakes and tires back on at the hangar.

Like you said, hope the rims were OK this time.

A high speed RTO is one of the most dicey things we train for, glad it worked out this time. :ok:

misd-agin
28th Aug 2015, 22:52
Rolling resistance?? How about speed brake drag? Reverse thrust?
110 kts is 2000-3000' down the runway. Anyone expect hot brakes/blown tires if they landed at 110 kts with 9,000-10,000' ahead of them?