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Topic: Why Pax Go To "Brace Position" For This Landing?
Username: Gonzalo
Posted 2013-04-10 17:52:35 and read 12950 times.

Hello All. I hope some of you can shed some light about this, I 'm a little intrigued about why the passengers of this flight were instructed by the cabin crew to assume "Brace Position". The flight was bumpy after hitting severe turbulence earlier in the flight and they had an engine off. But this is a twin engine jet. They spend 20 minutes in a holding pattern doing checks and trying to restart the engine, so there were no fears or signs of structural damage or similar. They never declared an emergency. Single engine landings are relatively common in twin jets...
I always thought that requesting pax to assume brace position is for emergencies when you think there is a good chance of going out of the runway, or hitting something in a forced, out of the field landing. But this is not the case.

Why is the crew requesting this ?? Is the standard or procedure similar where you work ??


http://www.avherald.com/h?article=4608f3ce&opt=0

Thanks in advance for your inputs !!

( Edited for typo )

[Edited 2013-04-10 18:04:12]

[Edited 2013-04-10 18:04:44]

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: trent772
Posted 2013-04-10 18:03:43 and read 12906 times.

Quoting Gonzalo (Thread starter):
Single engine landings are relatively common in twin jets...

Really? I don't think they're all that common.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: Gonzalo
Posted 2013-04-10 18:15:20 and read 12853 times.

Quoting trent772 (Reply 1):
Really? I don't think they're all that common.

Yes this "incidents" are "relatively common". Just take a look at the Aviation Herald site. You will see reports of "engine shut down in flight" ( for twin jets ) on a daily basis, even more than one incident per day very often. The thing that is not common, as far as I know, is the cabin crew requesting the pax to assume brace position for a landing that should be, IMO, a safe and controlled landing. Maybe I'm wrong, and if that is the case I hope someone can help me to know better ( that's the point of this thread   )

Rgds.
G.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: AR385
Posted 2013-04-10 18:58:09 and read 12695 times.

Quoting Gonzalo (Reply 2):
The thing that is not common, as far as I know, is the cabin crew requesting the pax to assume brace position for a landing that should be, IMO, a safe and controlled landing.

Without being a pilot, I´ll venture an answer: While single engine landings on twins MAY be common, I´m not sure about that, it still is a procedure that differs from the ordinary. Controlling an aircraft on landing wtih asymmetrical thrust has to be a bit more risky than doing it under normal circumstances. The potential for it to veer off the runway, among other things, are probably the reason for asking the passengers to brace. I could be wrong, but I doubt they would do it for fun.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: tonystan
Posted 2013-04-10 19:08:12 and read 12660 times.

Was there a full diagnosis made of why the engine failed? Was there a possibility that something more could be wrong with the aircraft somehow related to the engine (or indeed the turbulence) which could effect the performance of the aircraft and its ability to land and stop safely? Did the pilots feel confident or not in the stability of the aircraft considering the problem or did they feel the priority at such a late stage in the flight should be to just get the thing on the ground and worry about a diagnosis after?

Sounds to me that the pilots erred on the side of caution and did the right thing!

Iv been in incidents that required a brace but it was precautionary, better safe than sorry!

[Edited 2013-04-10 19:09:37]

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: rfields5421
Posted 2013-04-10 19:15:37 and read 12626 times.

First - it is a CRJ-200 - an aircraft without an excess of power under normal conditions. Any additional turbulence or issues of any kind on final approach, and the aircraft might not be able to go around. Resulting in a possible off field or off runway landing.

Second - the crew was unable to restart the engine - which would have been normal. That it could not be restarted raises the possibility of another issue which could make the landing dangerous.

Extreme caution on the part of the crew - yes. But not outrageously so.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: Gonzalo
Posted 2013-04-10 19:42:40 and read 12531 times.

Quoting rfields5421 (Reply 5):
First - it is a CRJ-200 - an aircraft without an excess of power under normal conditions. Any additional turbulence or issues of any kind on final approach, and the aircraft might not be able to go around. Resulting in a possible off field or off runway landing.

Probably I'm not understanding your words correctly or something like that... I can not believe that the aviation authorities would give a type certificate for a passenger aircraft that "might not be able to go around resulting in a posible off field or off runway landing" just because is landing with one engine and some wind gusts.

Quoting AR385 (Reply 3):
Controlling an aircraft on landing wtih asymmetrical thrust has to be a bit more risky than doing it under normal circumstances.

You have the rudder and the ailerons to compensate the asymmetrical thrust, and AFAIK, to get the approval / type certificate, every passenger twin jet must be capable of fly/land in one engine, tail mounted or not.

I guess the crew had its ( good ) reasons to act like they did, I'm only trying to see the things from a passenger perspective, and I can say for sure that probably 90 % of the flying public will be much more scared if you ask them to assume brace position....

In any case I want to thank you all for your opinions and inputs, it is an interesting exchange of opinions.

Best Regards!!
Gonzalo.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: AR385
Posted 2013-04-10 20:06:39 and read 12461 times.

Quoting Gonzalo (Reply 6):
You have the rudder and the ailerons to compensate the asymmetrical thrust, and AFAIK, to get the approval / type certificate, every passenger twin jet must be capable of fly/land in one engine, tail mounted or not.

Sure you do. And still, even with all their engines going, they´ve managed to veer off the runway. An AA DC-10 inbound from HNL did it in DFW and a US 734 at LGA on take off. So with one engine, it must not be too routine.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: PassedV1
Posted 2013-04-10 20:45:43 and read 12362 times.

Quoting Gonzalo (Reply 6):
Probably I'm not understanding your words correctly or something like that... I can not believe that the aviation authorities would give a type certificate for a passenger aircraft that "might not be able to go around resulting in a posible off field or off runway landing" just because is landing with one engine and some wind gusts.

I am sure I will be corrected if I am mistaken, but I do not believe there is a "single engine go-around" performance requirement under Part 25.

The two-engine go-around certification requirement is 3.X(2?) degree path from initiation of the go-around.

I think as a practical matter, the Accelerate-go certification requirements assure that if you had the performance to have taken off from a runway, you would have the performance to do a single-engine go-around off of a runway, so as a practical matter, I do not believe it would be relevant in this particular case since the airport in question is Kennedy. But I could imagine it being an issue if you were over the Rockies and had to divert into MSO or BTM....or over Central/South America where Density Altitudes can be well over 10,000 feet on normal days.

Although it may not be "uncommon". Although it may be something we train for. Make no mistake, a single-engine landing is an EMERGENCY procedure and indicative of the fact that you are having a VERY bad day.

So..

1. It is very possible that the airlines procedures require the brace position for all Emergency Landings.

2. It has to be in the back of the Captain's mind that the severe turbulence encountered could have caused structural damage that led to this engine failure making me question if I truly know the condition of my aircraft.

3. Like I said before, a single-engine landing is an Emergency Procedure on any jet. In my experience (I have zero on the CRJ) you are likely landing with something short of normal landing flaps...which means a higher approach speed and landing with visuals that you have only ever practiced in the simulator. It's also possible that not everything is working with an engine failed, although someone with specific knowledge of the CRJ would have to answer that one.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: trent772
Posted 2013-04-11 00:13:15 and read 12115 times.

Quoting Gonzalo (Reply 2):
Yes this "incidents" are "relatively common". Just take a look at the Aviation Herald site

Your assumption is laughable, there are millions of flights on "twin engine" airplanes on a daily basis, yet you claim that operations on a single engine are quite common, they're not, avherald.com is just a website that does its best to report aviation incidents all around the world. That's it.
The fact that you see a couple of IFSD on a single date means nothing if your going to leave out the other huge amount of uneventful flights that reach their destination without any problem.

Get your facts straight.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: CamiloA380
Posted 2013-04-11 01:07:44 and read 11988 times.

Quoting Gonzalo (Reply 2):
Yes this "incidents" are "relatively common". Just take a look at the Aviation Herald site. You will see reports of "engine shut down in flight" ( for twin jets ) on a daily basis, even more than one incident per day very often.

Spending too much time in AvHerald might lead you to think that one engine out landings are common, but ehh, no not really. Just figure out how many flights there are per day, around the world. And just because the pilots brief for an engine out situation prior to departure, does not mean it's common.

Fact is, AvHerald doesn't provide you with exactly EVERY incident/accident that happens in the world of aviation as you might think.
I don't see where AvHerald published the incident that happened in EFKT in 03.04.2013 with a Norwegian 738 that was fully established on the ILS 34 with A/P engaged and at 3250' the aircraft started a sudden climb with full thrust.

Plus I've heard/read really bad things about the owner of that website.  
Quoting trent772 (Reply 9):
The fact that you see a couple of IFSD on a single date means nothing if your going to leave out the other huge amount of uneventful flights that reach their destination without any problem.

Exactly.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: jayeshrulz
Posted 2013-04-11 01:22:45 and read 11953 times.

There is a big conspiracy theory behind this too.

It is said that people are told to brace so that it could protect the skull and also preserve dental records in case of a mishap. I dont know how far this is true, but nevertheless, people in the Air France A320 survived because they were in a brace position protecting the most valuable part of your body. Ie Head.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: pvjin
Posted 2013-04-11 01:28:20 and read 11943 times.

Quoting trent772 (Reply 9):
Your assumption is laughable, there are millions of flights on "twin engine" airplanes on a daily basis, yet you claim that operations on a single engine are quite common, they're not, avherald.com is just a website that does its best to report aviation incidents all around the world. That's it.

How you define common? Sure compared to amount of flights with no problems amount of flights with one engine failed is very small, however I'm pretty sure it's still way more common failure than many others, such as problems with flaps, landing gear and such. Sure every major airline gets engine flameouts every year.

Quoting CamiloA380 (Reply 10):
I don't see where AvHerald published the incident that happened in EFKT in 03.04.2013 with a Norwegian 738 that was fully established on the ILS 34 with A/P engaged and at 3250' the aircraft started a sudden climb with full thrust.
http://www.avherald.com/h?article=4603ef59&opt=0

Quoting CamiloA380 (Reply 10):

Plus I've heard/read really bad things about the owner of that website.

Like what? All I've heard is Ryanair bashing the site because it has truthfully reported about their incidents.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: CamiloA380
Posted 2013-04-11 01:44:53 and read 11891 times.

Quoting pvjin (Reply 12):
http://www.avherald.com/h?article=4603ef59&opt=0

Ok, replying on the phone maybe wasn't a good choice. 
Quoting pvjin (Reply 12):
Like what? All I've heard is Ryanair bashing the site because it has truthfully reported about their incidents.

An A.net member might want to tell you. It actually has been discussed before here on A.net. can't provide you with a link right now.

I am aware about the issue AvHerald had with Ryanair.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: Gonzalo
Posted 2013-04-11 03:50:44 and read 11699 times.

Quoting trent772 (Reply 9):
Your assumption is laughable, there are millions of flights on "twin engine" airplanes on a daily basis, yet you claim that operations on a single engine are quite common

My "assumption" is less laughable than your reading comprehension. I said this :



Quoting Gonzalo (Thread starter):
Single engine landings are relatively common
Quoting Gonzalo (Reply 2):
Yes this "incidents" are "relatively common".

Don´t you know what the word "relatively" means ?? Where is the wording "quite common" in my posts ? The one that should have their facts straight is you.

Quoting pvjin (Reply 12):
How you define common? Sure compared to amount of flights with no problems amount of flights with one engine failed is very small, however I'm pretty sure it's still way more common failure than many others, such as problems with flaps, landing gear and such. Sure every major airline gets engine flameouts every year.

  

Quoting PassedV1 (Reply 8):
2. It has to be in the back of the Captain's mind that the severe turbulence encountered could have caused structural damage that led to this engine failure making me question if I truly know the condition of my aircraft.

I thought that could be a reason for all the "brace position" thing, but I dismissed that when I saw they where circling 20 minutes in a hold doing checks. If you have doubts about structural damage or flight control surfaces you try to land ASAP.

Rgds.
G.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: tonystan
Posted 2013-04-11 04:26:09 and read 11590 times.

Quoting Gonzalo (Reply 14):
I thought that could be a reason for all the "brace position" thing, but I dismissed that when I saw they where circling 20 minutes in a hold doing checks. If you have doubts about structural damage or flight control surfaces you try to land ASAP.

You're clearly not a pilot, engineer or crew member!

Stop being so quick to shout down other people's comments about your posts!

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: Gonzalo
Posted 2013-04-11 04:54:15 and read 11503 times.

Quoting tonystan (Reply 15):
Stop being so quick to shout down other people's comments about your posts!

Says who ? This is a discussion forum. I can ask and reply whatever I want within the forum rules. If you don't like this rules, you are in the wrong place. Go and create your own private, closed to discussion forum, and see what happens.

And please tell us, the ignorant mass, what course of action you take when you are not sure about the structural condition of the aircraft. Maybe we can learn something new from your expertise.

G.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: trent772
Posted 2013-04-11 05:28:41 and read 11408 times.

Quoting pvjin (Reply 12):
How you define common? Sure compared to amount of flights with no problems amount of flights with one engine failed is very small,

You just defined it.

Quoting pvjin (Reply 12):
Sure every major airline gets engine flameouts every year.

We haven't had one in over four years.

Quoting Gonzalo (Reply 14):
Don´t you know what the word "relatively" means ?? Where is the wording "quite common" in my posts ?

Quite common or just common, you are wrong I'm afraid, the technology and reliability behind today's jet engines prevents this situation from being a "common" one.

Do you think aviation authorities would ponder the idea of ETOPS 330 if IFSD's were a "common" occurrence, let alone the concept of ETOPS as a whole?

The current approval standard for 180-minute ETOPS is 0.02 shutdowns per 1,000 hours of engine operation. That’s amounts to an in-flight shutdown rate of one every 50,000 hours.
Many of the world’s ETOPS operators are achieving 0.01 shutdowns per 1,000 hours or, for twinjets on eight-hour ETOPS flights (accumulating 16 hours of total engine time per flight), an average IFSD of one every 6,200 flights.

Now I don't think that's "common" but I will let you decide.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: tonystan
Posted 2013-04-11 05:56:51 and read 11316 times.

Quoting Gonzalo (Reply 16):

You're just rude!!!!!

Discuss but don't get on the defensive and shout someone down when they give you a perfectly understandable explanation!

[Edited 2013-04-11 06:00:14]

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: AR385
Posted 2013-04-11 06:13:29 and read 11154 times.

Quoting CamiloA380 (Reply 13):
An A.net member might want to tell you.

Two actually.   

Quoting jayeshrulz (Reply 11):
It is said that people are told to brace so that it could protect the skull and also preserve dental records in case of a mishap.

Interesting. Given today´s ID techniques, I think if that was ever true, it´s probably not anymore.

Quoting Gonzalo (Reply 16):
And please tell us, the ignorant mass, what course of action you take when you are not sure about the structural condition of the aircraft. Maybe we can learn something new from your expertise.

For one, the QF A380 that had its engine blow up after take-off form SIN spent close to an hour up in the air doing checks before coming in to land. Sometimes it´s better to try and see what king of structural damage is really there than rushing towards the runway without really knowing if the airplane is going to come apart when the landing gear comes down.

Quoting tonystan (Reply 18):
You're just rude!!!!!

No, not really. You do need a lot of patience, but he is not rude.

[Edited 2013-04-11 06:53:09]

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: KFlyer
Posted 2013-04-11 08:44:47 and read 9257 times.

My friend Gonzalo, I appreciate your hunt for perfection - but the crew had fifty lives in their hands, and it is always better to be safe than sorry. I indeed am no pilot or an engineer, but I assume that a CRJ200 will not have the same capability as a 777 when on single engine. Imagine expecting a Lamborghini's performance from a WV Beetle (of course, the Beetle has its own perks). Always better to be safe than sorry.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: Jpax
Posted 2013-04-11 09:11:47 and read 8948 times.

Quoting PassedV1 (Reply 8):
I am sure I will be corrected if I am mistaken, but I do not believe there is a "single engine go-around" performance requirement under Part 25.

As far as certification goes, I'm not sure. On the ATP ride, however, a single engine missed approach is a required maneuver.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: BoeingGuy
Posted 2013-04-11 09:58:04 and read 8358 times.

Quoting Gonzalo (Reply 2):
Quoting trent772 (Reply 1):
Really? I don't think they're all that common.

Yes this "incidents" are "relatively common". Just take a look at the Aviation Herald site.
Quoting trent772 (Reply 9):
Quoting Gonzalo (Reply 2):
Yes this "incidents" are "relatively common". Just take a look at the Aviation Herald site

Your assumption is laughable, there are millions of flights on "twin engine" airplanes on a daily basis, yet you claim that operations on a single engine are quite common, they're not, avherald.com is just a website that does its best to report aviation incidents all around the world. That's it.
The fact that you see a couple of IFSD on a single date means nothing if your going to leave out the other huge amount of uneventful flights that reach their destination without any problem.

Get your facts straight.

There aren't quite a million twin engine flights a day, but Trent has the right idea. Say there are 60,000 twin engine jet flights a day and Avheald reports one single engine landing a day. That's 1/60,000. It's probably more like 1/100,000 flights. I'd hardly call that relatively common.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: BoeingGuy
Posted 2013-04-11 10:02:32 and read 8328 times.

Quoting Gonzalo (Reply 14):
Quoting pvjin (Reply 12):
How you define common? Sure compared to amount of flights with no problems amount of flights with one engine failed is very small, however I'm pretty sure it's still way more common failure than many others, such as problems with flaps, landing gear and such. Sure every major airline gets engine flameouts every year.


Do you guys know anything about aviation safety statistics or are you just making things up? Do you really have any data that says engine failures are more common that flap or gear problems, or does it just sound like something fun to say?

What constitutes a flameout? Which types of engines can relight themselves, and which can't? I might suggest reading up on facts like this, because I'm pretty sure your assumptions are incorrect.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: JBirdAV8r
Posted 2013-04-11 10:15:19 and read 8149 times.

Quoting Gonzalo (Thread starter):
They never declared an emergency.

I don't see where they did not declare an emergency. An engine failure is an automatic emergency--especially if you don't get it restarted.

Quoting AR385 (Reply 3):
Without being a pilot, I´ll venture an answer: While single engine landings on twins MAY be common, I´m not sure about that, it still is a procedure that differs from the ordinary. Controlling an aircraft on landing wtih asymmetrical thrust has to be a bit more risky than doing it under normal circumstances.

Well, of course it's outside the ordinary and it takes away some margin of error, but I wouldn't describe it as being "risky" or even particularly difficult. The CRJ handles very well on one engine.

Quoting rfields5421 (Reply 5):

First - it is a CRJ-200 - an aircraft without an excess of power under normal conditions. Any additional turbulence or issues of any kind on final approach, and the aircraft might not be able to go around. Resulting in a possible off field or off runway landing.

That's not accurate on several levels.

First of all, even at heavy weights the CRJ-200 has a surprisingly ample amount of power down low. It's a pig above 20,000' or so, but it performs quite well down low.

And you'll have more energy in a single-engine go around sooner than you would in a takeoff with a V1 cut, which is absolutely a certification requirement.

Quoting PassedV1 (Reply 8):
I think as a practical matter, the Accelerate-go certification requirements assure that if you had the performance to have taken off from a runway, you would have the performance to do a single-engine go-around off of a runway, so as a practical matter, I do not believe it would be relevant in this particular case since the airport in question is Kennedy.

I believe your thinking here is correct, though I am by no means an expert on Part 25 certification requirements. See above.

Quoting rfields5421 (Reply 5):
Second - the crew was unable to restart the engine - which would have been normal. That it could not be restarted raises the possibility of another issue which could make the landing dangerous.

This part is correct, and I would guess that it factored into the crew's decision to have the passengers brace. In the CRJ, I'd not be worried as much about structural damage to the airframe itself as I would be the engines, especially if the airplane was handling fine. The engines on the CRJ-200 can be finicky when it comes to the way the air enters the engine. If the airplane encountered severe or extreme turbulence (which is a distinct possibility, as I've seen several urgent PIREPs over the past few days indicating the same, as well as enduring some bumpy rides) I could imagine a scenario in which the engine(s) could have actually flamed out and been automatically re-lit once, or even several times by the continuous ignition during the extreme turbulence. There's a possibility that the re-iginitions could have been so violent that they caused physical damage to the engines. That would explain the crew's inability to restart the failed engine, and as a pilot, it would have made me immediately quite suspect of the operative engine. Since there was ample time for the crew to prepare for a single-engine landing and make restart attempts, along with my suspicions that the operative engine might also be damaged, I would absolutely consider having the flight attendant teach the brace positions and prepare the cabin for an emergency landing.

I'll also add that in over 10 years and thousands of hours of flying, I've had ONE engine failure--and that's an anomaly. Most pilots I know have spent their entire careers without one.

Lastly, my goodness. We all had to start from square one, not knowing anything about airplanes--let alone knowing what a flight crew is thinking in a very specific scenario. The level of smart-aleckiness in these forums is really just sad. Let's all mature a little and get along.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: BA0197
Posted 2013-04-11 15:52:48 and read 5100 times.

From a passenger perspective, if I knew that the aircraft was flying with an engine inoperative, I have always said I would voluntarily assume the brace position. Better to be safe than sorry. Bravo to the crew for not taking any chances.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: okie
Posted 2013-04-12 08:55:00 and read 2851 times.

Quoting BA0197 (Reply 25):
From a passenger perspective, if I knew that the aircraft was flying with an engine inoperative, I have always said I would voluntarily assume the brace position

Obviously never been on a CRJ-200.
You have to be in the brace position to see out the window in any case, whether you are looking where you are landing or getting to see what you are going to crash into. 

Okie

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: spacecadet
Posted 2013-04-12 15:15:16 and read 2605 times.

As a passenger, I've been through one engine-out landing and it was most definitely treated as an emergency. Fire engines chasing us down the runway, etc. I honestly do not remember if we assumed brace position or not, but I don't remember actually seeing the landing so I think we probably did. The last thing I remember was peeking out the window and seeing the fire trucks and other emergency vehicles parked at the threshold and starting to move as we crossed it. I'm pretty sure I'd remember the landing itself if I actually saw it.

My first thought when I read this thread was "how does the OP know they didn't declare an emergency?" Also, even if you were listening to a scanner and didn't hear that, there can be different words used depending on the situation - a pilot doesn't necessarily need to say "I declare an emergency" to ATC. There are several other standard callouts that can achieve the desired effect from an ATC perspective, such as "pan pan" which may be more appropriate in a situation where the pilots aren't quite sure what they have other than an engine out. But on board that would be treated like any other emergency.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: CosmicCruiser
Posted 2013-04-12 15:33:15 and read 2562 times.

why does everyone always come up with these wild reasons for simple things. I would say the crew is just covering their butts. It's much easier to call for it and not need it than to wish you had called for it and didn't. When you're at the other end of the table answering questions the conservative decisions will look real good.

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: baw716
Posted 2013-04-12 16:43:20 and read 2465 times.

To answer the OPs question,

Depends on the situation...if it is not SOP (and since I can't know that), then the captain would have the discretion to order it based on his assessment of the situation. If there was severe turbulence and an engine out, it would not be unreasonable to brace in the event some unforseen event were to occur during the landing.

I don't view that as extraordinary.

As for the rest of the discussion...I'm not going to comment on it, since it doesn't bear on the OPs question.

baw716

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: Wisdom
Posted 2013-04-12 18:23:24 and read 2374 times.

Quoting PassedV1 (Reply 8):
I am sure I will be corrected if I am mistaken, but I do not believe there is a "single engine go-around" performance requirement under Part 25.

There is and it's called single engine missed approach climb gradient.
For a twin it's 2.1% under FAR Part 25.

Quoting jayeshrulz (Reply 11):

There is a big conspiracy theory behind this too.

It is said that people are told to brace so that it could protect the skull and also preserve dental records in case of a mishap. I dont know how far this is true, but nevertheless, people in the Air France A320 survived because they were in a brace position protecting the most valuable part of your body. Ie Head.

The head is important too, but the organs are also part of the most valuable.

But it really depends on the crash scenario, and the direction of the impact.

In simple terms, it's all about your spine and your blood.
The spine and your blood systems need to be oriented as flat as possible relative to the direction of the impact. The spine would otherwise be compressed beyond what it can bear.
Your blood vessels will have to bear much less force if the blood is locally pushed towards the direction of the impact than for instance all 5kg of your blood flowing at once towards your feet, causing the vessels to rupture and to bleed internally in your feet.

In the typical aircraft brace position, you cover both scenario's and since your body will create an angle close to 180 degrees at the area around the stomach, it will create a resistance for your blood flowing to your feet too fast in case of a vertical impact force.

There are only 2 weak links in the aircraft crash scenario that the brace position can't protect you from:
-You're more likely to be killed by debris, fire or explosion than by the impact force
-the current seat belt design is more likely to cause internal bleeding of your organs around the stomach area. The only good seat belts designs that protect your organs are shoulder harness/sparco type belts, as found on pilot seats in the cockpit, as they do not compress any organs, strongly increasing chances of survival and recovery.

[Edited 2013-04-12 18:26:10]

Topic: RE: Why Pax Go To "Brace Position" For This Landing?
Username: SEA
Posted 2013-04-12 20:11:43 and read 2251 times.

Quoting CosmicCruiser (Reply 28):
I would say the crew is just covering their butts. It's much easier to call for it and not need it than to wish you had called for it and didn't. When you're at the other end of the table answering questions the conservative decisions will look real good.

Exactly. Wouldn't everyone here prefer that their flight crew err on the side of safety?


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