Why are the flaps down on powered down aircraft ?
Posted by foxbat_s@reddit | aviation | View on Reddit | 230 comments
I was flying from berlin and noticed a embraer pull up beside my aircraft and shutdown, i noticed the flaps and slats were down. Is this normal for embrears ? What would happen if there is icing conditions or snow ?
WildmanJones172@reddit
Prevents build up of rain water when it’s not moving. Water adds a tremendous amount of weight . They can’t carry as many people then and it burns more gas, trying to carry the extra weight!
pedroordep534@reddit
A 319 came in recently in YYT, flaps left down due to weather conditions. Water flash froze on the underside of the forward flaps and behind the engine. Took us over an hour and 3 heaters to remove the ice. Fun times!
DeSchmiddi@reddit
Wow, OP is certainly getting down voted into oblivion.
Simple_Gold7606@reddit
We would leave them in the takeoff position on the ground in case of an evacuation on the P-3
Jeason15@reddit
Straight up, this is what I thought it would be. Also a P-3 alum…
Simple_Gold7606@reddit
4 fans of freedom!
Jeason15@reddit
Chips light on 3
pdxnormal@reddit
Maintenance, inspection, flap lube
nic-sfr@reddit
If maintenance needs the flaps down for routine inspections / lubrication, they usually do it themselves. Besides, Helvetic wouldn't have scheduled maintenance of this scope in Berlin
pdxnormal@reddit
Didn’t know the details. Thanks again
mottledmirror@reddit
I suspect it's because they've had an issue and engineering asked them to leave the flaps there or put them out. Doesn't look like an overly icy day to me but it could be anything.
There may also be a type specific requirement like an Airbus TAB requiring them to perform certain non standard procedures due to ongoing work on aircraft systems such as software.
EastCoastAV8R@reddit
Not relevant to this picture, but I've noticed a number of airlines SOPs (on the Airbus) is to leave flaps/slats extended in very warm weather. I was told (IIRC) it was to avoid spurious anti-ice bleed leak messages.
mottledmirror@reddit
Certainly was SOP on the A330 5-6 year ago not sure anymore
sloppyrock@reddit
This is correct. Very common in hot climates.
iamhadid@reddit
So they can get out of their seats easier
Muawaz-712012@reddit
not sure but on the A380 at Emirates, in cold conditions, flaps are kept down in cold environments to protect the aircraft from damage
Academic_Emu_5983@reddit
On a Boeing 727 the leading edge Krueger flaps, 2,3,6,7, are operated by hydraulic system A pressure. System A hydraulic pumps are engine driven so a parked 727 will have the 4 leading edge Krueger flaps drooped. Flown the 727 my whole career and never had an issue with accumulated snow/ice withe the aircraft parked overnight.
Particular-Law-9871@reddit
duh...its doing Pilotes
Montrama@reddit
Is there snow or icing conditions? AFAIK cold operations require you to not retract flaps before doing an outside inspection because snow that pushed by reverse thrusters can get between flaps and may damage them if you retract.
foxbat_s@reddit (OP)
No its not snow, its light rain. Metar as of posting (EDDB 04008KT 9999 -RADZ OVC005 02/01 Q1022 TEMPO 4500 -DZ )
I always assumed icing conditions could cause the mechanisms of flaps and slats to be blocked. TIL
DolphinPunkCyber@reddit
While water doesn't turn into ice at 2C at atmospheric pressure, these conditions are considered icing because thermometer is measuring temperature at one point, not every single point, and temperature can quickly change to actually icy conditions.
It's kinda like... we don't wait for roads to start icing up to change tires, add antifreeze, salt roads.
Fine-Hearing-7866@reddit
All the down votes for what lmfaooo
rvr600@reddit
Because visible moisture and 2C are icing conditions.
DolphinPunkCyber@reddit
Nope because at atmospheric pressure water/moisture does turns into ice at 0C.
So instead of downvoting the guy for saying something that is technically correct... just point out the nuance of why in practice it is considered icing condition.
Fine-Hearing-7866@reddit
How does this explain all the downvotes tho💀💀
WhiskeyTigerFoxtrot@reddit
This subreddit is filled with neurodivergents that worship aviation as a religion and get upset when every comment isn't 100% correct.
AutoModerator@reddit
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Delicious_Hurry8137@reddit
😂😂😂 made my day
RJH311@reddit
Wasn't a question asked looking for an answer?
Seems like an incorrect one would be fairly down voted
Not abnormal or unexpected...
This is how it's supposed to work
libmrduckz@reddit
my Army Airforce grandpappy woulda’ called ‘em shitsticks… because they are…
Typhoongrey@reddit
Half the time the most anal commentators are so unbelievably wrong or misinformed anyway.
Reacher-Said-N0thing@reddit
OrtimusPrime@reddit
You just described the comment section of any social media site.
LeCrimsonFucker@reddit
"This subreddit", better try all of reddit. A fucking case study for mob mentality.
BreadstickBear@reddit
I suppose not knowing that -2°C is 2 degrees Celsius below freezing is a capital offense.
Festivefire@reddit
If you think getting downvoted is the equivalent of getting taken out back and shot in the head, I think you need to spend less time on the internet, or at the very least, use a site that only has the updoot button instead of both.
Capitol offense indeed.
Downvoting USUALLY means nothing more than "I think you're stupid," or "I don't like that," or "I disagree," people aren't out there reserving their downvotes for only the most heinous crimes of the internet.
mylifeforthehorde@reddit
But people will skip downvoted comments . In this case it was an innocent assumption. He didn’t call for people to be executed.
Festivefire@reddit
You say that like it's a violation of their human rights for somebody to not read their comment. Who gives a fuck? If anything, that's a good thing, since it means there will be less people to downvote them now that they've received enough downvotes for reddit to auto-hide their reply. Nobody who actually cares about the thread of the conversation is going to skip OP's reply to a request for more information because it was downvoted, the only people who are going to skip it are the people who are going to continue to donwvote them for the crime of being wrong on the internet.
chromaticgliss@reddit
Downvoted enough comments are hidden. As someone with a casual interest in aviation that doesn't know particulars like this, I almost missed further explanation. This downvote behavior is actively preventing folks like me from learning.
afonsoel@reddit
I don't think people skip downvoted comments, but they definitely read them with "this guy prolly said something stupid" in mind
chromaticgliss@reddit
Downvoted comments are hidden in standard reddit. As someone with a casual interest in aviation that doesn't know particulars like this, I almost missed further explanation. This downvote behavior is actively preventing folks like me from learning from the further explanation that others provided.
Chaxterium@reddit
I never skip past downvoted comments. Quite the opposite actually.
ShantyUpp@reddit
Upvote for you sir! (Because I agree with your comment!👍)😂
ShantyUpp@reddit
If I see a huge downvoted comment I always have to read it!! 😬
superfriendlyavi8or@reddit
*capital. A capitol is a building that houses the legislative function of a government
sensor69@reddit
But that's not important right now
whepsayrgn@reddit
The Reddit vote intent/etiquette says this shouldn’t be downvoted since it’s contributing to the conversation. Yeah OP misunderstood but since they communicated their thoughts we can see why.
Downvoting someone for not knowing or misunderstanding something on a question thread that THEY MADE is not the best way to use the feature.
“Vote. If you think something contributes to conversation, upvote it. If you think it doesn’t contribute to the community it’s posted in or is off-topic in a particular community, downvote it.”
Not a death sentence to hit a thumbs down but that doesn’t mean people are using it in a way that builds the community.
quax747@reddit
Read what's written, not what you want to read.
It's 2 degrees. Not -2 degrees. Icing conditions direct require sub 0 temperatures. Icing conditions is temperature at our below 5 degrees with visible moisture in the air.
flightist@reddit
Plenty of operators define it as <10c.
quax747@reddit
Tre, true
MatrimVII@reddit
It is pretty stupid, and downvotes mostly reflect what people think about your comment. In this case, people think it's stupid. Nothing very complicated really.
God_Damnit_Nappa@reddit
Because this sub is full of elitist assholes that think you should already know everything there is to know about aviation. People here are not inclined to help you out if you're a beginner or just someone with questions
oddballrandomwords@reddit
I think you misspelled Neurodivergent (elitist assholes).
airfryerfuntime@reddit
Think of it like a bunch of clowns dog piling on some random person.
foxbat_s@reddit (OP)
Yeah exactly, i don't understand. Good old reddit downvote train i guess
Festivefire@reddit
"Is there snow or icing conditions?"
"No it's not snow, *proceeds to list PERFECT icing conditions*"
They simply do not want to spend the time to actually type out a message telling you they think you're stupid, so they downvoted you as a quick alternative.
God_Damnit_Nappa@reddit
You'll note that 2C is above freezing so it's reasonable for someone that doesn't know anything about aviation or weather to assume that means it's not icing conditions. But nah why correct someone when you can call them an idiot and just downvote. This sub is the absolute worst sometime with the elitist assholes like you here
Festivefire@reddit
Oh so I'm an elitist for actually explaining why he's being downvoted? Fine, next time instead of upvoting and explaining why theyre doing it, I'll just downvote and move on then, fuckwad.
Mun0425@reddit
You wrote what i was trying to give a damn to write for an hour lol.
Western-Sky88@reddit
I gave you a sympathetic up vote because we've all been there.
Shark-Force@reddit
Reddit moment
2wicky@reddit
REDD1 270G99KT 0000 -SHCY OVC000 M99/M99 Q0001 NOSIG RMK TROLLS WIDESPREAD FREEZING COLD BRR
Breakdown of "REDD1 METAR":
"Reddit International"
Winds from the west at 270°, gusting to 99 knots — a massive storm of opinions and arguments.
Visibility is zero meters — you can't see anything through all the sarcasm and downvotes.
Light showers of icy cynicism — classic Reddit vibes.
Overcast skies at ground level — completely smothered in negativity.
Temperature and dew point are both at -99°C — absolute zero, Reddit-style coldness.
Atmospheric pressure is 1 hPa — the weight of the collective downvotes crushing all hope.
No significant changes expected — Reddit stays cold and inhospitable.
Tldr Not a good day to comment in my opinion.
le_spectator@reddit
I hate to be that guy… but I can’t stand it.
Absolute zero is -273°C/-459°F If the weight of the downvote is crushing everything, then the pressure should be higher, more like Q9999hPa
2wicky@reddit
Reddit International appreciates your feedback, and while we regret the discomfort we have caused you, our official policy is that we take no accountability for any misleading information we present. That said, if you are interested in accurate data that has been peer reviewed by our dedicated community, I would like to point you towards the comment above that you yourself wrote as it appears to have been thoroughly fact checked. Your welcome.
theonlysafeaccount@reddit
When able, we have a number for you to take down.
Electric_Bagpipes@reddit
I’ll be honest, this is good.
Blue_Dominion@reddit
This is golden!
foxbat_s@reddit (OP)
Hahaha, this is nice !
Zany-ISP@reddit
Holy downvoting what did you even say here that was bad?!
SiouxPilot65@reddit
It doesn’t have to do with thrust reversers kicking up snow, you both are on the right track though that it has to do with preventing flap/slat damage. If you pick up ice while on the approach, the procedure in the Embraer is to leave the flaps deployed until deicing with type 1 or a visual inspection shows no ice accumulation.
It’s 2° C and raining at the surface which means there’s a high likelihood that icing conditions exist on approach/departure.
Source: I fly the 170/175.
i_farding@reddit
Not at my company. This an e2 thing or something?
SiouxPilot65@reddit
Nope, it’s entirely possible that it’s a company to company practice. Honestly, if it’s just light ice on approach and if it’s above freezing at the surface, I’ll just bring them up anyways.
Creepy_Truth_9000@reddit
Why is this downvoted so bad?
arathorn867@reddit
Wasp nest in the instrumentation made his comment crash
Stypic1@reddit
Why did this get downvoted so much haha
rangerbeev@reddit
Could be wet wing.
MrNightmare_999@reddit
Damn! r/downvotedtooblivion
VajainaProudmoore@reddit
Anything below 5 degrees and with visible moisture is potential for icing.
BenRed2006@reddit
2°C and rain can meet freezing
Mun0425@reddit
Temp at 2C is warrant for ice checks
friedrice33@reddit
They leave them down in snowy conditions so maintenance can look and confirm there’s no build up before they retract the flaps. Retracting the flaps with ice and snow build up can cause airframe damage.
foxbat_s@reddit (OP)
No its not snow, its light rain. Metar as of posting (EDDB 04008KT 9999 -RADZ OVC005 02/01 Q1022 TEMPO 4500 -DZ )
I always assumed icing conditions could cause the mechanisms of flaps and slats to be blocked. TIL
SkyHighExpress@reddit
Geez, what nonsense are people talking about here and down voting the dude. Sure, inspect the flaps in snow but in icing conditions of 2c and rain????? Sure, I will just call engineering for an inspection when it’s 9c and raining as that’s icing conditions too. Might get me the rest of the day off as I’m taken to the funny farm. In reality, they probably got a warning, hit a bird or just forgot. It might be know that I may pulled onto stand with the spoilers still up and gotten an embarrassing spoiler fault message after engine shutdown. I deny everything
assiprinz@reddit
Light rain on a supercooled hull turns into ice pretty quickly, even if it’s positive degrees outside
foxbat_s@reddit (OP)
Okay, this can happen in ground too ? I thought it always happened in air ?
rambyprep@reddit
If the fuel were cooled in the air it can happen on The ground
i3urn420@reddit
Yup, I've seen many wings freeze up after a jet comes down with -10c fuel in the wings.
foxbat_s@reddit (OP)
Right ! It makes sense, thanks
rckid13@reddit
Anything under +10C with any visible moisture including rain and mist requires us to run the anti ice systems for taxi and takeoff. In America The FAA defines icing conditions as temperatures between -40C and +10C where any visible moisture exists. So that would include flying or taxiing through rain, snow, mist or clouds. It also includes any time we taxi through a puddle or snow on the ground. We run anti ice in all of those situations.
Ungrammaticus@reddit
Why stop at minus 40?
That’s extremely cold, but still not the minimum temperature I’d expect to occur in e.g. Alaska.
rckid13@reddit
It's because at that temperature the air is so dry that not enough liquid should exist to be able to stick to the aircraft. If you look up METARS for Antarctica they typically don't report a dew point in the winter because it's so dry that there is no moisture so there is no dew point.
The minimum temperature authorized for takeoff and landing in most commercial jets is -40C, so if it does happen to be below that we can't takeoff and land anyway. The minimum temperature for most de-ice fluid is slightly warmer than that even, so we also run into issues deicing when it's below about -30C. The holdover times can be just a few minutes, or not exist at all. This is why in most places you'll see "regular" commercial flights cancel below about -30C. Obviously there are some cargo operators and special aircraft that operate into the really cold places in the arctic and Antarctic but it's not regular United and Delta planes. Those operators are specially trained and they're using special procedures and equipment.
boston_jorj@reddit
That was awesome. I learned something today. Thank you.
Ungrammaticus@reddit
Thanks for the detailed answer!
foxbat_s@reddit (OP)
Thanks, that what I misunderstood. I was thinking the icing rules is for only when flying. That also explains the massive downvotes also 😅
moosehq@reddit
The fuel is supercooled and can cause ice on contact with rain.
BreadstickBear@reddit
Is the ambient temperature below the freezing point of water wherever you are?
If yes, it's icing conditions.
SRM_Thornfoot@reddit
If they suspected ice buildup on the arrival they would have left the flaps down for the taxi in, the outside ground temperature and the fact that it was raining on the ground would not be a consideration.
KingLeo92@reddit
Why are you asking questions if you refuse the answers?
aeroatlas117@reddit
Why are you getting downvoted for stating the conditions?
hobbyhoarder@reddit
Probably because they misunderstood that those conditions don't prevent icing.
nineyourefine@reddit
Right, so rather than upvoting for visibility and a teaching moment, downvote to -837465 because he asked a simple question.
hobbyhoarder@reddit
I agree with you, once anyone gets a downvote or two, I feel others just do it automatically.
darps@reddit
reddit threads often seem to become massive OP downvote threads for no reason at all, it seems. I don't get it either.
wrestlingnutter@reddit
Why so many down votes?
SRM_Thornfoot@reddit
That weather report actually indicates icing conditions. Anything under 10c with visible precipitation or a temperature / dewpoint spread of less than 3c has the potential to cause icing in the engines where the pressure drop in front of the running engine can cause the temperature to drop below freezing and the air to become supersaturated with moisture. Maybe you have seen videos of engines with fog being created in their intakes on takeoff. That could be creating ice too, so we run with engine anti ice on under those conditions.
AresV92@reddit
In Canada now we are inspecting for clear ice up to 15°C. Last year we had a CRJ900 with clear ice on its wingtip tanks during light rain at 13°C. We also had ice ridges from melting and refreezing underwing fuel frost on an A321 at 20°C. It only happens when they tanker in fuel and it's cold from flying up high. The fuel can get down to -40°C some days. You also need the right moisture level lower down for the ice/frost to form in the first place.
SuspiciousAK@reddit
Or someone just forgot the after landing flow 😉
RamiHaidafy@reddit
Yup. I was recently on an Etihad A320 flight where the pilots forgot to raise the flaps after landing.
There's no snow in the Middle East so that certainly can't be a reason. 😂
xxJohnxx@reddit
The A320 has a limitation were you have the flaps at Flap 1 if the OAT is more than 30°C. This is to prevent some nuisance caution message: https://www.pprune.org/tech-log/648614-airbus-a320-flaps-retraction-extension-hot-weather.html
Could also easily have been a bird strike. We are not supposed to retract the flaps after one to prevent a dead bird getting crushed into the mechanical systems.
RamiHaidafy@reddit
That link says the flaps are retracted from position 1 at the gate. The flaps were not retracted here, at all, they were at landing config.
The temperature was certainly lower than 30 C. It's "winter" now.
I can't rule out a bird strike though, but it doesn't appear to have been the case. Even the spoilers were not retracted until we were almost stopped at the gate. Genuinely seems like they forgot.
Hdjskdjkd82@reddit
Happens more often than people think.
Chaxterium@reddit
I've never forgotten!! Not once! Especially not on a plane where the flaps are hydraulic and it doesn't have electric hydraulic pumps so we had to spool one of the engines to get the flaps back up....nope....never happened....
StandardMortgage833@reddit
The hydraulics can’t hold them up, they’re down because there’s nothing keeping them up
Chaxterium@reddit
The flaps are electric on the Embraers.
StandardMortgage833@reddit
Either way there’s nothing holding the flaps up after a complete shutdown
Chaxterium@reddit
Well in 20 years of flying airplanes I've never once seen flaps droop after powering off the plane.
StandardMortgage833@reddit
Ah. I stand corrected
Chaxterium@reddit
You had me thinking though. Because although I know for a fact that the flaps don’t droop, I can’t tell you what mechanism keeps them in place once power is removed. It’s honestly not something I’ve looked into and it’s not in the flight manuals that I can see.
I’m sure it’s in the maintenance manuals though.
xxJohnxx@reddit
Most of the transport category planes have their flaps driven by jackscrew. Most jackscrews are not reversible by design and hence the flaps won‘t droop once the actuators loose power. Some also have brakes on the jack screw mechanisms.
sloppyrock@reddit
For starters Id say there's a huge mechanical disadvantage in either direction. A bit of weight on the jack screws is not enough to back drive a hyd motor or electric motor via a gear box.
StandardMortgage833@reddit
Aight, I’m probably going to look into it, thanks for bringing it to my attention! Have a good day.
Chaxterium@reddit
If you find anything let me know! I’m curious now.
Have a good one!
StandardMortgage833@reddit
Thanks, will do!
tzwicky@reddit
Maybe it's a Swissair way of doing things???
xxJohnxx@reddit
Nothing in this picture has to do anything with Swissair.
Helvetic is a seperate company. Swissair does not exist anymore, large parts of it are now operating as Swiss International Airlines however.
unexpanded@reddit
So… why couldn’t they stay extended all the time while on the ground?
I can understand it makes it more difficult for the traffic to pass by etc, but beyond that?
xxJohnxx@reddit
On many aircraft the fuel trucks can only fit under the wings if the flaps are up. We normally like to have some fuel, so that‘s a good reason to retract them. Also it reduces the risk of other ground vehicles striking part of the flaps while maneuvering around the airport.
ywgflyer@reddit
You don't save anything by not retracting them -- you're going to have to change the flap setting for takeoff anyways, landing flap is typically "full flap" (whatever that is for the type of aircraft) and takeoff flap is much less than that.
Plus, now having flaps dangling down like that greatly increases the chance they'll be damaged by ground equipment.
woodywoodchucknorris@reddit
So there isn’t as much hydraulic fluid in the lines.
Prata2pcs@reddit
Airectile dysfunction
LawKnown1380@reddit
Damn FO left them down. Rookies
lcarsadmin@reddit
Parking Brake
Chaxterium@reddit
Sorry but what do you think the parking brake has to do with the flaps?
lcarsadmin@reddit
Just a joke...
Chaxterium@reddit
....I see.....
lcarsadmin@reddit
You know how in a manual transmission car you have to put on the parking brake and put it in 1st (or reverse) so it wont roll away? Well what if you had to put the wings in "park"
I bet its *extra funny* now that Ive explained it. 😁
Chaxterium@reddit
You're right! It is!
xylarr@reddit
They're tired, they're having a rest
PrestegiousWolf@reddit
To stretch them out. Wings and flops get tired.
Strict_Lettuce3233@reddit
Hydraulics
Chaxterium@reddit
The flaps are electric on the Embraers.
Spectre130@reddit
Powered down? Sure looks like the position lights are on.
foxbat_s@reddit (OP)
Engines off, so the hydraulics maybe powered down
n00ik@reddit
Flaps are electric, so it wouldn't really matter if there is hydraulic power or not
Anarolf@reddit
flaps are typically hydraulic in large aircraft, with an electric backup motor (very slow)
Some1-Somewhere@reddit
It is very dependant on aircraft type. On all the FBW Airbuses, for example, flaps are powered solely by green/yellow hydraulic systems, with backup being to operate at half speed with only one hydraulic system. There is no electric backup other than starting the electric backup hydraulic pump(s).
Anarolf@reddit
indeed I did…. I used the word “typically” tho! other comments point out E170 etc are electric mains. Definitely learned something new.
ywgflyer@reddit
They're electric in the E170/190 family.
n00ik@reddit
Ok, maybe typically, but on the E190, which is the plane in question, they are electric
HumbleSiPilot77@reddit
The only time we put the flaps down like this on ground was when they needed to be inspected. In the Ejet powering down the AC doesn't do anything to flaps.
RareDragonfruit5335@reddit
So they won't drift away, I guess.
11ish@reddit
They're tired from flapping..
IndependentPrior5719@reddit
Canada population increase in comparison to g7
IndependentPrior5719@reddit
Oops brain fart
dutchcourage-@reddit
Few reasons. May have had a suspected wildlife strike and left them down for an inspection.
TheFl4me@reddit
This may or may not be my operator in OPs picture 😉
and this may or may not be an extract from our SOPs:
„Snow, ice or slush may accumulate on the flaps during landing roll or taxiing on contaminated surfaces (including surfaces treated with ice control sand), or in case of prolonged operation in icing conditions with flaps extended. Do not retract the flaps unless they are free of snow ice or slush.“
PreviousGrapefruit73@reddit
Their just tired.
cheng-alvin@reddit
I've never heard of this....I've seen airbuses with the flight controls down since there is no hydralic pressure but never the flaps
FluffusMaximus@reddit
Fun fact: I know you’re asking about airliners, but on the Super Hornet we put flaps down as part of our shutdown checks.
Spaghettiknivesthe2@reddit
Because I forgor💀
ParsnipRelevant3644@reddit
The ailerons on modern aircraft will droop after a while from hydraulic fluid pressure bleeding off, but flaps are driven into position by a jackscrew, so if the flaps are down, they were put there.
Also, on older planes, if one aileron is down, the one on the other wing is likely up.
Khischnaya_Ptitsa@reddit
Because there's no power to lift them up
b00c@reddit
plane thinks ground personnel are its chicks, so it's trying to protect them.
Puzzleheaded_Cut_656@reddit
🥹aww🥰
Shot_Independence274@reddit
you sir have my upvote!
and/or, pilot did what i do in my car all the time, cut off the engine while the wipers are working and halfway!
foxbat_s@reddit (OP)
Lol 😆
sassinyourclass@reddit
Because the plane is sad. You should go give it a hug
Extreme_Weather4007@reddit
Ive seen this happen on a plane I was on after landing in Puerto Vallarta. I wonder if sometimes they forget lol.
randomtroubledmind@reddit
They're resting. It's tiring to hold your flaps up all the time.
mfknLemonBob@reddit
No idea for jumbos, but when i worked on ospreys the flaps would “fall” after we shutdown because the hydraulics weren’t powered and nothing was holing them in the 0 position.
Super-Skymaster@reddit
What I like about Reddit is finding the people I’ve always been curious about - like Osprey techs.
I describe Ospreys as “4 million parts spinning in ways that piss off Newton, the Wright Brothers and Sikorsky."
mfknLemonBob@reddit
Not too far off the point. Pass press aside, it’s an amazing aircraft. I enjoyed my years working on them. My 2 cents: biggest struggle it faces is dealing with pilots who i have to tell: “its a helicopter not an airplane. Also, its an airplane not a helicopter” then seeing their faces.
“Old” pilots were champs and never brought them back broken. But new folks thought they were fighter pilots and treated it accordingly. It has come a long way from the horror days of the early 2000’s.
Super-Skymaster@reddit
I’ve come to respect them. But I really think it was a unfair burden to expect all those techs come up to speed on its unique characteristics when even the engineers designing it were still working through the fine points.
It always seemed like it was being Beta-tested live.
mfknLemonBob@reddit
No doubt. I felt it when working on wiring harnesses. Just based off how they routed them, you can tell they built it from the outside in: chasing the form-factor and not functionality/engineering sense.
QuantityRelative4980@reddit
This series airplane uses electric flaps.
Frog_Prophet@reddit
That doesn’t happen on these airplanes. They’re mechanically locked in each position.
h5n1zzp@reddit
He is squawking 7500
Chaxterium@reddit
Nope. That's not what that means anymore.
b33fstu@reddit
That’s what I thought! Isn’t flaps down at the gate signal for 7500?
Chaxterium@reddit
Used to be. Not anymore. Many manufacturers recommend leaving the flaps down after landing on a runway contaminated with ice or snow (or taxiing in those conditions).
This is because it's possible that ice or snow could have accumulated in the flap actuators and could cause damage when raising the flaps. So we leave them down and inspect them before raising them.
DomTheHun@reddit
I always assumed no power=no hydraulic pressure to keep the flaps up, but I’m sure I’m wrong
Chaxterium@reddit
That is indeed wrong. Firstly the flaps on the Embraers are electric and secondly, even on aircraft with hydraulic flaps they are held in position mechanically. They don't droop once hydraulic pressure is lost.
janXD@reddit
Because it's not turned on.
Chaxterium@reddit
Well you gotta wine and dine it first.
MyNameIsRuffles@reddit
I have heard that sometimes the flaps are left in the takeoff config of the next flight to save time on turnaround
Chaxterium@reddit
This may be true for some operators (none that I've ever worked for) but it doesn't really save any time.
zadiraines@reddit
I’d guess pre-flight inspection?
Chaxterium@reddit
Nah. We don't lower the flaps for pre-flight inspections on transport category aircraft. That's more of a GA thing.
WombatAnnihilator@reddit
Things just kinda sag later in life. Don’t judge
Far_Dragonfruit_1829@reddit
But you don't see this on B-52
WombatAnnihilator@reddit
If they don’t sag, maybe they had cosmetic lifts. Again, no need to judge.
Far_Dragonfruit_1829@reddit
You're probably right. Most BUFFs have had obvious work done.
DJ_Hindsight@reddit
They’re resting
Far_Dragonfruit_1829@reddit
Pining for the fjords
Final_Size_4011@reddit
Gravity
wApzor@reddit
Wait till you see a 787 with droopy flaperons
Sarahsfeet15@reddit
I fly the A350 and we would occasionally do this if there are icing concerns. Although looking at the photo, looks likely it could be a maintenance issue
Frank_the_NOOB@reddit
During icing conditions it’s better to leave the flaps down as a precaution. If the flaps have ice on it, retracting them could cause component damage
Schafman80@reddit
So flaps and slats have to be extended for take offs for extra lift. Pilots routinely forgot, and lead to aborted takeoffs. Airlines changed it to be a part of their pre-departure checklist, and now you see flaps and slats extended during taxi.
It was a pain for me when I ran a large de-icing operation because flaps and slats were required to be retracted during deicing. Why? Because type IV fluid builds up in the area in front of the flaps and creates a gummy substance there. I had to ask several aircraft a night to retract before we sprayed.
cosmicpop@reddit
I think it's more that fly-by-wire aircraft probably have electrically actuated control surfaces, so when the power gets turned off, the weight of the surfaces just pulls them downwards. Control surfaces with mechanical linkages or hydraulics are all connected together so balance eachother out.
You'll also see this happening with modern military aircraft as the control surfaces are all actuated by motors.
Chaxterium@reddit
This is incorrect. The flaps do not droop when the power is off.
cosmicpop@reddit
you're right, sorry, specifically flaps don't droop. However other control surfaces can and do droop.
Chaxterium@reddit
Absolutely!
Im-Not-A-Number@reddit
Mx
zachb657@reddit
Could just be maintenance doing some work
sell_out69@reddit
Our SOPs calls for the flaps to be retracted to position 3 on the 170/175 when you suspect severe ice accumulation on approach to prevent damage.
ParkApprehensive9028@reddit
Airbus hyd bleed down
andrea-3006@reddit
Probably some bird strike happened, they leave the flaps down for the maintenance to inspect them especially the deploymentmechanism, or maybe some flaps system failure that again requires maintenance to investigate before retracting them and making things worse. Sometimes it's just some flaps failure indication showing up in the cockpit
billy123765@reddit
Most likely this, bird strikes require inspections and putting the flaps down is part of the inspection process.
bd_whitt@reddit
Not familiar with the E190 but what I fly has an icing stipulation that says “if aircraft will be cold soaked or exposed to extended icing, do not retract flaps”
It’s mainly so they don’t become frozen to the aircraft because our de-icing protocol requires them to be down So the fluid run off will cover the crevice in the split flap so ice doesn’t dislodge into the flap control area when we raise them after take off.
This is my best guess. Flaps can be forgotten if you get busy but not very likely. All my flows are so engrained into my autopilot muscle memory that I actively have to stop myself from doing them if a non-normal procedure calls for it.
HA4T-PJ-GEC1@reddit
Depending on the OAT it could have been in order to do a visual inspection
Bad_Karma19@reddit
It's possible they just failed to raise them after landing.
LounBiker@reddit
Possible, but unlikely.
More likely the post landing checklist has an entry like 'if possible icing conditions leave flaps extended'
galacticspacecaptain@reddit
Could be for birdstrike inspection
TheCodeWizard@reddit
This guy just reminds his ppl days where you lower flaps to get out of the aircraft
InquisitorNikolai@reddit
Because the plane is tired, so it doesn’t have the strength to hold them up any more.
s2mario@reddit
Getting ready for replay mode
foxbat_s@reddit (OP)
Lol I get that reference
LCARSgfx@reddit
Could be down for a bird strike check. It happens every now and then. This is the only way to check all surfaces for damage if a bird strike or suspected bird strike is reported by the incoming crew.
BIue_Ooze@reddit
Their arns get tired too
D0ntC4llMeShirley@reddit
Given the weather I doubt it’s due to icing or freezing conditions. That plane will have done a 1 hour flight from Switzerland, which isn’t enough for the wing to get supercooled.
It could be one of 2 things, a bird strike which was mentioned above. And it needs an inspection. Or the pilot forgot to put them up 🤣
foxbat_s@reddit (OP)
Maybe ! This was the weather as of posting
EDDB 090750Z AUTO 04008KT 9999 -RADZ OVC005 02/01 Q1022 TEMPO 4500 -DZ
autosave36@reddit
That's icing conditions to the letter. +10 to -40c in visible moisture.
ventus1b@reddit
My guess is that with the engines off there’s no hydraulic pressure for the actuators to keep them up. Why should ice/snow affect ‘hanging’ flaps differently?
CarbonCardinal@reddit
You don't pull the flaps up until maintenance can inspect the areas to confirm they are clear of any moisture blown in there by the reversers, which can freeze and jam them if the flaps are brought up. They don't droop that much just from the hydraulics being off.
ventus1b@reddit
Thanks for the clarification.
AStove@reddit
I'm not sure about which types of aircraft but don't some have overwing exits that require the flaps to be down?
kilimanjarojetti@reddit
This is called hydraulic lock-in. Whilst the aircraft hydraulic system is de-energized, the control surfaces may hinge downwards because the pressure of hydraulic fluid is low, but it is still high enough to prevent the surfaces from being moved violently by the wind.
commandercody_76@reddit
Not sure what the Embraer manual says, but at my airline on the 737 if we suspect ice accumulation on the flaps we are supposed to leave them extended about half way when we taxi in. This allows a mechanic to make sure no ice would be in the way of them fully retracting, if there is it would have to be cleared before bringing the flaps up.
george8310@reddit
Maintenance or bird strike inspection