Hail before V1

moxiepilot

moxiepilot

Well-Known Member
So here a question generated by something I saw today. Thunderstorm 5 SW of the field moving NE over the field starts throwing out pellets of hail. The captain must have been taxiing during this event.

As the hail increases to nickel size hail the 747 began its takeoff run and departed to the NE, away from the TS.

One minute later the hail on the field was golfball size (no exaggeration) it was coming down like rockets and if you were unlucky enough to be outside it would've hurt, a lot.

So, if you were the FO when the captain elected to takeoff in the above scenario - would you call an aborted takeoff with the increasing hail size?
 
inb4 Monday morning quarter backing.

Got a flightware link?

I personally wouldn't have taken off with a storm 5 miles away, moving towards me in the first place, depending on the storm and other conditions... But I'm a Sally. YMMV, we can discuss it if you want. Internet arguments are always entertaining. :) Hail falling out of a storm 5 miles ahead of it isn't a weak one. That being said, I've seen hail with blue skies above, but that was before I knew what a low precipitation supercell was. That could have been what was going on.

At any rate, I abort for any abnormalities. Hail is a definite abnormality. To me at least. Turning away, hopefully right away, was one good decision out of this.
jtrain609 said:
Fo's can't call an abort where I work, so...no.
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Really? Even our Korean "FOs" can call for it. Captain performs it though.
 
UAL747400 said:
inb4 Monday morning quarter backing.

I personally wouldn't have taken off with a storm 5 miles away, moving towards me in the first place, depending on the storm and other conditions... But I'm a Sally. YMMV, we can discuss it if you want. Internet arguments are always entertaining. :) Hail falling out of a storm 5 miles ahead of it isn't a weak one.

At any rate, I abort for any abnormalities. Hail is a definite abnormality. To me at least. Turning away, hopefully right away, was one good decision out of this.

Really? Even our Korean "FOs" can call for it. Captain performs it though.
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So, I'm assuming you brief that in your take off briefing, then? I've never had anybody brief a high-speed abort for hail. Lose an engine, etc., yes, but have never been briefed on that one.

If you don't brief it, how are you calling for a high speed abort without meeting a requirement for the abort as briefed? Just curious, as it's an academic discussion now...probably 5 pages in a few days, but for now, let's discuss.
 
Stone Cold said:
So, I'm assuming you brief that in your take off briefing, then? I've never had anybody brief a high-speed abort for hail. Lose an engine, etc., yes, but have never been briefed on that one.

If you don't brief it, how are you calling for a high speed abort without meeting a requirement for the abort as briefed? Just curious, as it's an academic discussion now...probably 5 pages in a few days, but for now, let's discuss.
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Not hail specifically. Just any abnormality. My brief specifically is "We will abort prior to rotation(no V1 on a 99) for any red annuciators or abnormalities, either pilot can call abort abort abort, I will perform the abort..." In this case, it'd be an abnormal noise. ;) Or in other words, me pooping my pants and needing to go change them. :)

I don't fly a 747 either, so that may or may not weigh in as well. I assume a high speed abort in a 747 is a big deal and might not be worth doing vs getting a few dents. Maybe the heavy guys can chime in.
 
Look up the (I believe) South Carolina Lear 60 accident with blown tires. Above 80 until V1, in most jets, requires a specific briefing, and I will not abort for anything other than 1. Fire, 2. Engine failure, 3. T/R deployment, or 4. Loss of directional control (at least in the jets I have flown). There might be company specific other abort criteria, but spooky sounding hail (or was it heavy rain...can you tell the difference on the roll?) on takeoff is not a good reason for a high speed abort. I will NOT abort for a blown tire unless the directional control becomes an issue.
 
You have a point. Aborting in a 99 and even landing on the remaining runway shortly after rotation wouldn't be a big deal on a long runway.

Nickel sized hail, I might be able to tell on the 99 windsheild or plexi in a GA plane. Don't know about a triple pane window.
 
In the case of hail, unless there are abnormal engine indications, predictive windshear, or the airplane is damaged to the point that it won't fly (highly unlikely), the takeoff would continue once above 80 knots.

Where I work, FOs call abnormalities, CA calls for an executes the reject if necessary. I'm certain this is the Boeing standard, being that a high-speed reject in a heavy is a significant event. Best case, the brakes are melted. Worst case:

tncj6.jpg
 
moxiepilot said:
So here a question generated by something I saw today. Thunderstorm 5 SW of the field moving NE over the field starts throwing out pellets of hail. The captain must have been taxiing during this event.

As the hail increases to nickel size hail the 747 began its takeoff run and departed to the NE, away from the TS.

One minute later the hail on the field was golfball size (no exaggeration) it was coming down like rockets and if you were unlucky enough to be outside it would've hurt, a lot.

So, if you were the FO when the captain elected to takeoff in the above scenario - would you call an aborted takeoff with the increasing hail size?
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If I was concerned about the weather I would have said, "Hey Skipper, I think we ought to wait for this thunderstorm to blow by." (I don't like the idea of taking off into the face of one of these monsters, unless the alternative is worse.)

Where I work FOs may only call out abnormalities; the Captain decides, calls for and performs the reject.
 
I don't get the issue if they were taking off AWAY from a storm. And, if you didn't take off when there are cells within 5 miles of the field, often times you'd never go anywhere all day long.
 
Same where I work. If an FO sees any abnormality, he/she calls it out to the captain and the captain decides whether to abort or not. The captain accomplishes all aborts.

That said, if a prebreifed abort item occurs and the captain does nothing (incapacitated behavior), then the FO is to accomplish the abort under the assumption that the captain is incapacitated. I sure as heck would. The only problem is that by the time incapacitation is established, the airplane could already be above V1 and the takeoff should be continued at this point.

To the scenario at hand, our company is not authorized to depart when "hail is actually occurring" so game over right there. As for departing in the vicinity of a thunderstorm, if it is five miles away, it is well within range of our takeoff roll to cause wind shear especially if it is moving quickly (gust front). Even if you are taking off away from it, imagine 165 kts being turned into 135 kts INSTANTLY once you get owned by a microburst. Five miles would probably put you just about under the anvil depending on the size of the storm and the speed of the upper level winds so no, I would not depart in this scenario until we were upwind of the storm and if that means we don't go anywhere "all day", hey, that's aviation.
 
mmannfol said:
Same where I work. If an FO sees any abnormality, he/she calls it out to the captain and the captain decides whether to abort or not. The captain accomplishes all aborts.

That said, if a prebreifed abort item occurs and the captain does nothing (incapacitated behavior), then the FO is to accomplish the abort under the assumption that the captain is incapacitated. I sure as heck would. The only problem is that by the time incapacitation is established, the airplane could already be above V1 and the takeoff should be continued at this point.

To the scenario at hand, our company is not authorized to depart when "hail is actually occurring" so game over right there. As for departing in the vicinity of a thunderstorm, if it is five miles away, it is well within range of our takeoff roll to cause wind shear especially if it is moving quickly (gust front). Even if you are taking off away from it, imagine 165 kts being turned into 135 kts INSTANTLY once you get owned by a microburst. Five miles would probably put you just about under the anvil depending on the size of the storm and the speed of the upper level winds so no, I would not depart in this scenario until we were upwind of the storm and if that means we don't go anywhere "all day", hey man, that's aviation. We're paid to deal with the weather, not disregard it.
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I hand the baton off to you good sir! :)
 
In my posts, I was merely responding to the abort criteria. Whether or not they should have left the gate, or stopped taxi, is an entirely different subject. Who knows what the crew were experiencing...did the hail hit them, or was it isolated to the OP's viewpoint first? Did the hail ever actually hit them (the crew)? If so, we'll probably eventually see pics of a 747 with hail damage.

Like I said previously, this could be a very long topic if other areas are explored.
 
Stone Cold said:
In my posts, I was merely responding to the abort criteria. Whether or not they should have left the gate, or stopped taxi, is an entirely different subject. Who knows what the crew were experiencing...did the hail hit them, or was it isolated to the OP's viewpoint first? Did the hail ever actually hit them (the crew)? If so, we'll probably eventually see pics of a 747 with hail damage.

Like I said previously, this could be a very long topic if other areas are explored.
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Oh I wasn't disagreeing with you.

How about this, would a cracked windshield be a reason to abort at or below V1? I can definitely see the reasoning for having absolutes with high speed aborting between yours and daselbens posts. I have no idea what it takes to crack those thicker windshields, though I have seen a demonstration of a baseball bat hitting a Dash 8 windshield without cracking. *shrug*
 
UAL747400 said:
Oh I wasn't disagreeing with you.

How about this, would a cracked windshield be a reason to abort at or below V1? I can definitely see the reasoning for having absolutes with high speed aborting between yours and daselbens posts. I have no idea what it takes to crack those thicker windshields, though I have seen a demonstration of a baseball bat hitting a Dash 8 windshield without cracking. *shrug*
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Below 80. Panes crack every once in a while even at altitude, so no need for a high speed reject. Even a side window opening above 80 isn't a reason to stop.
 
dasleben said:
Below 80. Panes crack every once in a while even at altitude, so no need for a high speed reject. Even a side window opening above 80 isn't a reason to stop.
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It will get wet loud and nasty, but stopping or being distracted by it is a larger threat than continuing.
 
dasleben said:
Below 80. Panes crack every once in a while even at altitude, so no need for a high speed reject. Even a side window opening above 80 isn't a reason to stop.
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Oh I've seen that video too! Looks windy! :)

What I was getting at was hail being big enough to crack windows. Going beyond the original scenario and encountering large hail right away. I would assume there's other damage happening as well.(?) Perhaps there wouldn't be any indication problems initially with the engines, or any signs of airframe degradation, but if time slowed down enough, I might think that something would be going boomy boom soon and consider aborting. Whatchya think?
 
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