The great big "ask an airline pilot" thread!

15-02-2021 2:03pm

OK. Thanks.
Following on from the MTOW question can an officially de-rated 777 200 ER take off from Dublin and make it to East Coast North America.

smurfjed · 15-02-2021 3:49pm

What do you mean by officially derated?

Boeing 777’s have two type of derated thrust, fixed derate usually (10-25%) and these are selected by selecting TO-1 or TO-2nin the FMC. On top of this, they have another method called “assumed temperature method”, this basically tells the engine that the outside air temperature is hotter than it actually is and the engine therefore delivers less power. The 2 ratings can be combined so that the engine is operating at around 55% of the installed thrust.

The last time I checked the numbers for Dublin, aircraft could easily get to the west coast.

15-02-2021 3:55pm

"777-200ER
Aircraft landing approach. Side view of a twin-engine jet in flight with flaps and landing gear extended.
A 777-200ER of British Airways, its launch operator
The B-market 777-200ER ("ER" for Extended Range), originally known as the 777-200IGW (increased gross weight), has additional fuel capacity and an increased MTOW enabling transoceanic routes.[80] With a 658,000 lb (298 t) MTOW and 93,700 lbf (417 kN) engines, it has a 7,065 nmi (13,084 km) range.[177] It was delivered first to British Airways on February 6, 1997.[81] Thirty-three customers received 422 deliveries, with no unfilled orders as of April 2019.[2]

As of July 2018, 338 examples of the -200ER are in airline service.[10] It competed with the A340-300.[178] Boeing proposes the 787-10 to replace it.[179] The value of a new -200ER rose from US$110 million at service entry to US$130 million in 2007; a 2007 model 777 was selling for US$30 million ten years later, while the oldest ones had a value around US$5–6 million, depending on the remaining engine time.[180]

The engine can be delivered de-rated with reduced engine thrust for shorter routes to lower the MTOW, reduce purchase price and landing fees (as 777-200 specifications) but can be re-rated to full standard.[181] Singapore Airlines ordered over half of its -200ERs de-rated"

smurfjed · 15-02-2021 4:03pm

Pretty much all airliner engines come “derated”. The only smaller engines that I remember for the B777-200 were for the early versions, I think that the engine thrust was 76,000 lbs. these were the first aircraft that BA retired from service.

goingnowhere · 15-02-2021 7:24pm

The poster asking the question seems to be the hunt to find out if a 'US' carrier running DUB-US with a 777 has been playing around with the MTOW for ATC fees.

1. The 777-200 ER has ~50 MTOW more than the plain -200, so you could register at a significantly lower MTOW as you won't need that extra 50 tons out of Dublin to East Coast US

2. If you are running a 777-200ER at -200 weights then you clearly could do a derate (Boeing)/flex (Airbus) take off within the operational limits set down by the operator and manufacturer. If you are talking about actually going into the engine FEDEC and swapping some jumpers and making max trust lower so 100% is not 100%. The 737NG has this where the engines are plugged to a certain level but if you firewall the thrust levers it will give you max design thrust

Airbus tried to offer a regional A350, lower thrust, lower MTOW. You could then pay for some nice person in Airbus to visit, give them another briefcase of cash and they would tinker with the systems and enable insane mode to get you a full A350.

15-02-2021 7:32pm

goingnowhere wrote: »

The poster asking the question seems to be the hunt to find out if a 'US' carrier running DUB-US with a 777 has been playing around with the MTOW for ATC fees.

1. The 777-200 ER has ~50 MTOW more than the plain -200, so you could register at a significantly lower MTOW as you won't need that extra 50 tons out of Dublin to East Coast US

2. If you are running a 777-200ER at -200 weights then you clearly could do a derate (Boeing)/flex (Airbus) take off within the operational limits set down by the operator and manufacturer. If you are talking about actually going into the engine FEDEC and swapping some jumpers and making max trust lower so 100% is not 100%. The 737NG has this where the engines are plugged to a certain level but if you firewall the thrust levers it will give you max design thrust

Airbus tried to offer a regional A350, lower thrust, lower MTOW. You could then pay for some nice person in Airbus to visit, give them another briefcase of cash and they would tinker with the systems and enable insane mode to get you a full A350.

I'm just asking because the 777-200er is really cheap now and for specific missions might where not reaching the limits of its range be better than a 787 or 330 or 789. Obviously anyone who can legally reduce charges they should.

TP_CM · 22-03-2021 4:31pm

I have a general flying question.. When an aircraft is coming in to land during bad weather and, at the last minute, is struggling to get the wheels on the ground maybe due to air speed or a sudden gust of wind, instead of a go-around, why aren't the engines thrown into reverse thrust? It seems like that reverse thrust is only employed when the wheels are on the ground only. If you're a few feet from the ground, is it not tempting to turn on the reverse thrust? Is the reason due to safety? Or because it would not be effective?

basill · 22-03-2021 4:56pm

Use of reverse thrust in the air in the situation you describe would likely lead to at best a hard landing and at worst a crash and collapse of the landing gear and other related structures.

Airborne use of reverse thrust generally only features on military aircraft and typically is used to increase rates of descent into war zones to avoid ground to air threats whilst simulatenaously deploying chaff.

Modern commercial jet transports reverse thrust is engaged by a combination of weight on wheels and spoiler activation to avoid inadvertent airborne deployment.

Fritzbox · 22-03-2021 5:06pm

TP_CM wrote: »

I have a general flying question.. When an aircraft is coming in to land during bad weather and, at the last minute, is struggling to get the wheels on the ground maybe due to air speed or a sudden gust of wind, instead of a go-around, why aren't the engines thrown into reverse thrust? It seems like that reverse thrust is only employed when the wheels are on the ground only. If you're a few feet from the ground, is it not tempting to turn on the reverse thrust? Is the reason due to safety? Or because it would not be effective?

well, Russians (or former Soviets at least) like to do it that way...

goingnowhere · 22-03-2021 5:30pm

Concorde and the Trident were certified for reverse trust in flight, DC8 inner engines could be reversed in flight. You get a fairly insane decent rate...

737 can select reverse below 10 feet radar alt

Once selected in the flare you better be sure to land...

de biz · 22-03-2021 9:03pm

I remember Flight Safety telling us about a GIV Captain deploying the buckets on finals to Palma!VERY lucky to recover....

smurfjed · 22-03-2021 9:41pm

remember Flight Safety telling us about a GIV Captain deploying the buckets on finals to Palma!VERY lucky to recover..

it isn’t designed from work in the air and is governed by a weight on wheels system called a nutcracker.

bkehoe · 22-03-2021 9:55pm

TP_CM wrote: »

If you're a few feet from the ground, is it not tempting to turn on the reverse thrust? Is the reason due to safety? Or because it would not be effective?

Presuming use of reverse in flight was permitted on an aircraft, generally once you select reverse thrust you've committed to the landing. Up until selection of reverse, a go around is still an option. And if you've 'floated' past the touchdown zone the last thing you want to be doing is committing to a landing from which you potentially cannot stop before the end of the runway as the calculations the crew will have performed will usually have been on the basis of wheels touching tarmac about 300m from the start of the runway. If you ever watch a commercial aircraft training with touch and goes (landing and shortly taking off again) you'll see the reversers are never deployed for the same reason - no guarantee of ability to quickly provide forward thrust once the actuators start to deploy the reversers (it takes several seconds).

A comment here suggests it's possible on the 737. This is correct but only due to systems redundancy - it's impossible to deploy the reversers as long as the aircraft is in 'flight' for safety and use of reversers in flight is prohibited (even below 10ft). In case the normal weight on wheels sensors for the air/ground logic do not function as normal the system is designed to also use the radio altitude.

goingnowhere · 22-03-2021 11:38pm

Fairly sure it is possible on all first generation jets though not in the book as authorised, the unfortunate Lauda 767 incident refocused the industry.

Several US airlines for a while permitted/allowed push back using reverse trust on the 727/DC9/MD80 families

Markus Antonius · 18-06-2021 10:38pm

I'd like to know when pilots are going to pull together and discuss the obvious

1123heavy · 20-06-2021 11:29am

Markus Antonius wrote: »

I'd like to know when pilots are going to pull together and discuss the obvious

??

Tenger · 20-06-2021 9:51pm

Markus Antonius wrote: »

I'd like to know when pilots are going to pull together and discuss the obvious

If this is any of the utter tripe I have seen on twitter over the last week there will be a forum ban involved

EchoIndia · 20-06-2021 10:30pm

goingnowhere wrote: »

Fairly sure it is possible on all first generation jets though not in the book as authorised, the unfortunate Lauda 767 incident refocused the industry.

Several US airlines for a while permitted/allowed push back using reverse trust on the 727/DC9/MD80 families

Types on which reverse in flight was possible and permissible were the Douglas DC-8 and HS.121 Trident. There was a discussion of this on the Pprune forum recently. https://www.pprune.org/aviation-history-nostalgia/640540-raf-vc-10-flight-reverse-thrust-use.html

1123heavy · 20-06-2021 11:52pm

Tenger wrote: »

If this is any of the utter tripe I have seen on twitter over the last week there will be a forum ban involved

I genuinely have no idea what is being discussed here but this now has increased the curiosity

A quick explanation or even a PM if acceptable would be much appreciated!

Edit: disregard, a quick google of "twitter pilot" seems to have revealed it

Markus Antonius · 21-06-2021 5:34pm

Tenger wrote: »

If this is any of the utter tripe I have seen on twitter over the last week there will be a forum ban involved

Don't know what that story is about. I'm talking about an apparent "gag order" on pilots discussing certain things or speaking with the media at all under threat of termination of contract or even worse.

I'm sure reasons are for "security" purposes but I want to know the extent of this order and what exactly they are not allowed discuss...

L1011 · 21-06-2021 6:32pm

There's not a chance you're going to get info on that here. So please stop trying.

1123heavy · 21-06-2021 10:43pm

If it means anything, I am a pilot employed in an airline and I have received no gagging order nor has anyone told us not to speak to any media (are they even trying to speak to us!?)

Whatever it is I can assure you it is not anything of a hot topic among the community otherwise we'd be aware

Strumms · 21-06-2021 11:09pm

I’m not a pilot but any company I’ve worked for including an airline, we were simply told to give the email for Public / media Relations ....and make no comment....

lintdrummer · 21-06-2021 11:11pm

Likewise, I don't know of any gag order on any airline staff. Would such a thing even be possible? Most employees in any large organisation are bound by a social media policy, but that's generic.
Would Markus Antonius care to elaborate on what specifically pilots are not supposed to be talking about?

1123heavy · 21-06-2021 11:38pm

Strumms wrote: »

I’m not a pilot but any company I’ve worked for including an airline, we were simply told to give the email for Public / media Relations ....and make no comment....

Yes that is always the case I believe, but it seems the poster is indicating in the last week or so some notice regarding a specific incident has gone out and we aren't to discuss it with the media

Tenger · 21-06-2021 11:56pm

Markus Antonius wrote: »

Don't know what that story is about. I'm talking about an apparent "gag order" on pilots discussing certain things or speaking with the media at all under threat of termination of contract or even worse.

I'm sure reasons are for "security" purposes but I want to know the extent of this order and what exactly they are not allowed discuss...

So all the airlines across the globe (or is it just Europe?) have issued the same "gag order" for the same reason?
We have pilots on this forum from at least 4 different airlines. Somehow I doubt they all got the same "order".

Sounds very QAnon-adjacent to me. (a global cabal keeping secrets from the sheep population)

smurfjed · 22-06-2021 11:56am

So are we now officially banned from talking about Chemtrail dispersal procedures ?

basill · 22-06-2021 3:40pm

Likewise we have no "gag order" in our airline. What we do have is a social media policy. We also have people within the organisation who are specifically trained in dealing with media requests and who will be "on message".

Markus Antonius · 30-06-2021 11:16pm

lintdrummer wrote: »

Likewise, I don't know of any gag order on any airline staff. Would such a thing even be possible?

basill wrote: »

Likewise we have no "gag order" in our airline. .

This is exactly what someone with a gag order would say :pac:

Tell me then what the real stance is on the so called "Santa's Shortcut". I've heard some ridiculous claims about weather being too bad (despite most commercial planes flying above weather systems) and also other things like radiation exposure and navigation systems going cuckoo when flying too close to magnetic north

Seems like a big fish story to me

Growler!!! · 01-07-2021 10:48am

Markus Antonius wrote: »

Tell me then what the real stance is on the so called "Santa's Shortcut". I've heard some ridiculous claims about weather being too bad (despite most commercial planes flying above weather systems) and also other things like radiation exposure and navigation systems going cuckoo when flying too close to magnetic north

The real stance? What you're referring to is called Polar Ops by those of us who operate that far north. In the distant past large twin engine aircraft had to remain within 1 hours flying time of a diversion airport. As reliability increased, ETOPS was extended dependant on routes/ aircraft and operator to a max of 207 minutes on the type Im qualified on. Air New Zealand have a max ETOPS certification of 330 minutes or the ability to operate on a single engine for 5 1/2 hours!! The Santa Shortcut is used by many airlines to reduce flight times to the US west coast.

The weather is generally quite calm in that region but you will have misinterpreted the term "bad" when referring to the weather. As an aside modern jets tend to fly above most weather but not all. During monsoon season its not unusual to see thunderstorms with tops extending up to 60 thousand feet! Polar weather will refer to the extremely cold polar airmass which aircraft will spend a significant time in. This causes problems for fuel if the fuel temperature reduces close to its freezing point (for example jet A freezing point is -40 degrees C). Dispatchers will reroute aircraft away from such cold air masses. If the fuel temp gets close to the freezing point and sets off a caution message then a decent into warmer air or a rerouting will cost time and fuel.

Space weather affects polar flights and indeed all flights but more so in polar regions. This can affect radio signals and cause black outs, solar radiation can expose pax and crew to more radiation than normal. The NOAA have a very good website describing this: https://www.swpc.noaa.gov

Nav systems don't quite go cuckoo anymore. Modern nav systems will switch over to True north when the aircraft goes above a certain latitude. If this fails there is the TRU button in front of the Captain which does the same thing but manually.

Boeing produced a very good article in their Aero magazine (link below) a number of years ago which covers the major issues with Polar ops. Can I suggest that you read and understand this as it is quite informative and is all open source information. It is readily available to non aviators as is everything else unless its a company specific policy.

http://www.boeing.com/commercial/aeromagazine/aero_16/polar_story.html#4

basill · 02-07-2021 1:18pm

Tip to the OP.....The magnetic north pole ain't where you think it is and is constantly on the move. And get off the conspiracy channels on youtube.

Markus Antonius · 06-07-2021 10:53pm

basill wrote: »

Tip to the OP.....The magnetic north pole ain't where you think it is and is constantly on the move. And get off the conspiracy channels on youtube.

It's exactly where I thought it was and how is it being on the move got any relevance to my question?

Board Walker · 23-05-2022 8:50pm

Hi Guys.

Just wondering are there any A330 Captain's/FO's that use Microsoft Flight Simulator 2020?

Obviously it does not matter which airline you fly for.

I have been asked by an acquaintance who is developing the A330 for same to do some flight testing of the flight model/Physics of the aircraft behavour.

It's for a well established developer in the simulation development sector.

PHOEBEKEELY · 21-06-2023 4:51pm

I once asked Denis Slattery how much he'd charge to haunt a house??? He didn't respond. He only died in May of this year at the age of 98.

Astral Nav · 21-06-2023 9:43pm

https://www.boards.ie/discussion/comment/120745620#Comment_120745620

A legend and gentleman (even if he was a tad pedantic). Certainly left a legacy to Irish aviation. May he rest in peace and all the navigation stars shine brightly above him.

smurfjed · 28-06-2023 6:36pm

An absolute legend who got so many of us through the exams. May he RIP.

03-10-2023 12:31pm

Not sure where the best place to ask this question may be, so thought perhaps here.

I was on a flight the other day and the usual happens, where one of the pilots needs to go to the toilet and a member of cabin crew enters the flight deck. One thing crossed my mind, which was the need for this process to begin with. I believe it started after that intentional crash of Germanwings flight 9525.

Then I started to wonder, what benefit does this relatively new process actually have?

Let's say, for example, that a rogue pilot intended on crashing a plane in the same way, just quicker. What difference would having a member of the cabin crew in the flight deck have in such a situation? After all, I assume it could take as little as a minute to down a plane?

So my question is: is the change that happened actually effective, or is it done for optics?

Because otherwise I cannot see a situation where a rogue pilot couldn't down an aircraft in the same way that happened with the Germanwings flight (again, assuming the pilot wanted to down it far quicker). I also just learned that many German airlines dropped the rule 2-years after the Germanwings crash anyway.

I would be particularly interested to hear what airline pilots consider on this question.

EchoIndia · 03-10-2023 1:42pm

I doubt you'll get many professionals replying to such a question. The most obvious thing to me is that the cc member could presumably open the cockpit door as required.

artanevilla · 03-10-2023 1:44pm

It's an added layer of protection to help mitigate the risk of the cockpit door being locked.

03-10-2023 1:48pm

https://www.boards.ie/discussion/comment/121188752#Comment_121188752

https://www.boards.ie/discussion/comment/121188762#Comment_121188762

Germanwings and other German airlines dropped this requirement in 2017, so clearly these airlines do not see the merit of this added "layer of protection".

It's a legitimate question to ask if the security that it's supposed to provide is of any meaningful value at all.

If it was meaningful, then it wouldn't explain why some airlines dropped the requirement.

EchoIndia · 03-10-2023 3:05pm

https://www.boards.ie/discussion/comment/121188795#Comment_121188795

Unless you actually know why some airlines changed their practice, I think you are just surmising. You have apparently rejected the two responses you received and have ignored what was said.

de biz · 03-10-2023 6:00pm

https://www.boards.ie/discussion/comment/120779104#Comment_120779104

Denis's archive has been donated to the Shannon Aviation Museum.

IngazZagni · 04-10-2023 9:22am

Sometimes the reason this is done has absolutely nothing to do with the reasons you mention. It can be to do with the lack of cctv so the pilot can't see who is trying to get in without getting out of their seat. Also it has happened before were a pilot on a 737 tried to open the door but was moving the switch beside it which was the rudder trim and the plane ended up in an upset condition. This wouldn't happen if a cabin crew member was there etc.

04-10-2023 10:26am

https://www.boards.ie/discussion/comment/121192188#Comment_121192188

Fair enough, I hadn't considered those reasons.

I assumed that because it was introduced immediately after the German crash, that it was directly linked to that and that alone.

MarkN · 04-10-2023 12:31pm

https://www.boards.ie/discussion/comment/121192473#Comment_121192473

Many airlines did it before Germanwings, Ryanair being one. But as a professional pilot told me before, a male pilot (for example) will probably be able to overpower a member of cabin crew should they wish to do something reckless or indeed use some of the fire escape tools to incapacitate. A rare occurrence, thankfully.

I've also sat in 1A on an EasyJet and noticed a male cabin crew member hold up an item similar to a weight bag like you'd get in a gym for doing leg lunges outside the flight deck door while a pilot went to the jacks.

04-10-2023 12:38pm

https://www.boards.ie/discussion/comment/121192962#Comment_121192962

I've also sat in 1A on an EasyJet and noticed a male cabin crew member hold up an item similar to a weight bag like you'd get in a gym for doing leg lunges outside the flight deck door while a pilot went to the jacks.

Why was this, though?