Nepal air crash 2

[LittleInch]

Air crash in Nepal.

A bit down this link is a few seconds showing a severe wing dip and from eye witnesses the plane rolled.

Doesn't seem to have a lot of flap on and apprentice the co pilot only had 100 hrs.

New airport.

https://www.theguardian.com/world/2...ourning-announced-as-recovery-effort-restarts

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[dik]

Thanks, Alistair...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JohnRBaker]

Alistair, is this what your 'office' looks like:

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Alistair_Heaton]

yep you can't see it but there is funkie arm rests down the sides next to the stick.

Not only that, I have flown that very aircraft.

 

[Alistair_Heaton]

This is doing the rounds.

STOL stands Short Takeoff and Landings normally but in this context we can only assume they mean restricted approaches with higher than normal approach gradients more than 3 degs and short runways due terrain in the approach sector.

Stabilized approaches have come from years and years of data analysis of landing accidents. They basically require you to be full configured, checks done and in side the target speed for landing which is +30 -0 of your Vref (speed 50ft over threshold) roll inside certain limits (this is slightly different with circling approaches which is a whole different level of risk compared to a normal approach)

The examiner thing is a international thing in some nations where your 6 monthly check is observed by a none qualified examiner on type. For example in the ME I was checked by a A340 examiner on the Jetstream 41 and he had never flown a turboprop in his life. It doesn't occur in the USA or EU. But this one seems to say the local examiners all have to be checked externally so the old boy networks can't let failures through. So ATR examiners in Toulouse would have to test all the local examiners.

The rest of it is to do with flight time limitations and is for trying to limit fatigue.

The stabilised approach stuff is pretty obvious due to them being under 500ft and not yet pointing at the runway.

The rest is things that they have picked up doing the initial operator check.

Quite what an augmented flight crew duty is I have no clue. An augmented crew is used in ultra long haul were you have relief pilots on board or even a complete second crew but that only kicks in on 10 hour plus flights (I think I have never done that sort of ops) and I can't really see how that could be a feature for ATR pilots that the plane can stay in the air a max of 5 hours.

 

[zeusfaber]

I read that as "augmented duty time" rather than "augmented crew".

A.

 

[dik]

I'd always thought that small runways, in out of the way places were built on a slope to allow planes that were taking off... to roll downhill and for landing to be slowed by the uphill gradient. Is that not correct?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Alistair_Heaton]

No its just they can't get them flat with the airports.

zeus, augmented duty time means your duty time is extended due to being able to being replaced in flight by another pilot and your able to rest. Normal starting at a nice time of days is max 13 hours which reduces after more than 2 sectors. If you start in the middle of the night it drops down to 9 hours. I thik the current max duty world wide is 19 hours and they have a different crew for takeoff and landing. But take what i have said with a pinch of salt, I have never been near that sort of ops. There is a position called cruise pilot who are only qualified to fly the aircraft above 10k or 20k ft. Who can sit in the cockpit with a unrestricted pilot. Quite what training they do and qualification I have zero clue apart from they need the basic commercial pilots license and instrument rating. AF477 was using argumented crew and the Captain was in his bunk when it all kicked off.

ATR is short haul so to get anywhere near the max duty time you will have to get on the ground at some point which means you can swap to another crew without carrying them. Unless they were making people sit in the back and swap sectors down route and counting that as rest. Which I might add wouldn't be legal EASA not sure if FAA allows it or not. Once we go over 5:30 flight time then a slip crew has to get involved or one crew flys the first sector then goes to a hotel while another crew flys the next two and then first crew flys home after a split of 5 hours in a hotel. Which may result in a 15 hour day for all. But they don't like doing that because they then have to rest you for the previous duty time 15 hours so they loose 2 crews for 30 hours which is extremely expensive.

It doesn't make sense to me full stop never mind in relation to a short haul turboprop.

Anyway its obviously dodgy as hell what ever it is if they are wanting it banned.

 

[dik]

Thanks, Alistair

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Alistair_Heaton]

The stabilisation stuff Turboprops in Europe its usually 500ft all airfields and Jets 1000ft. Turboprops its a lot easier to get rid of excess energy and they are are all under 40 tons and the engines can react much quicker than turbofans, The old days on the JS32 we basically used to hammer in at max speed 230knts until 4 miles and then put the prop rpms up and power idle and we would be back at Vref +10 by 500ft with a full load on the glide. Q400 if you weren't below 210knts by 8 miles you were not landing. A220 you need to be back at 210knts by 12 miles and it will be tight.

Q400 I had to have a very quick mind shift when I started flying it. Even though the limit was 500ft I was always stabilised by 1000ft if you were tight and using the +30 knots at 500ft you just ate the runway in front of you. And you really couldn't have more than 15 deg bank angle because the stall speed would increase more than 30 knts. So there was no way in hell I would attempt to roll wings level at 500ft which was pretty much standard with the Jetstream. The stall protection didn't used to trigger on the Jetstream but I suspect we were closer than we knew. EFIS on the Q400 we had yellow and red zones on the airspeed indicator so we could see how close we got. The ATR has the same analogue instrument airspeed indicator as the Jetstream.

Truth be told the approach didn't actually look that unusual for the Jetstream, Must have done 100's if not thousands similar. Q400 no chance of attempting it. But I suspect this profile was normal in Nepal with the ATR. Q400 I would be aiming for 6 miles 1500ft rolling out on the glide speed about 160 knts (the ground speed was under 100kts in this case) Final stage of flap and back to Vref +10 at about 140 knts.

I might add ATR's are extremely slow in Europe on approach you just eat the separation if you carry on flying normal speeds. If there is one 12 miles in front I just come back to 160 knots ASAP and 99% of the time the controller will tell us to come back to final approach speed before 6 miles because we are catching them so quickly.

 

[Alistair_Heaton]

Just to compare old V new cockpits....

Here is concord

 

[Brian Malone]

Your not wrong, but then again the modern aircraft are designed to be managed not flown manually

This YouTube channel, 'Just Planes' has some amazing videos. This is just one of many they have that illustrates (at least to me) modern wide body passenger planes are very complex and automated machines and due to their size, speed, and safety requirements have to be flown by checklists, protocols, and rote, repetitive training. They are not anything like a small personal plane where you get the 'seat of the pants' feedback, etc. Alistair's comment makes sense to me after watching the JP videos.

https://youtu.be/JIsaleuGTYM

I have gotten hooked on the various full length flight videos and like many of them show preflight checkout, etc. And there is not overbearing 'music' or fake drama in many of the videos.

 

[Alistair_Heaton]

Not just Wide body if you look at the modern training aircraft such as the DA42 twinstar which they are doing multi training on.

https://res.cloudinary.com/engineering-com/image/upload/v1675580914/tips/wvkioMVeaGF__KHYtE6Zt0XNrc_v2amE0_5ndgMgyqc_z5j0da.webp)

Its the same these days.

 

[Brian Malone]

Alistair_Heaton got it! You know the ins and outs of aircraft piloting. Thanks!

 

[Alistair_Heaton]

I really don't disagree with the comment.

I am an auld fart and feel it these days.

The modern training has multiple changes since I went through and instructed. I do have a different skill set to the recently trained pilot. But then again they come with other skillsets more developed that I had to self learned over 1000's of hours and which may be incorrect.

Old school was extremely hands eye feet and tech, virtually no soft skills or communication skills. Their soft skills and communication skills are developed much earlier than mine were.

Just look at the Concorde picture three people required to run that lot with a seriously in depth knowledge of aeronautics and engineering. What killed it? The personalities of the pilots flying it, lack of communication etc soft skills.

Go to AF477 and its the opposite, failure to do lesson 10B in the PPL training which is usually about 5 hours in pre solo.

I might add that lesson and lesson 11 spin avoidance is the likely subject in this crash.

I learned very early on my gut feel and thoughts are not backed up by statistics, some of my similar vintage colleagues still haven't. This move away from primary eye, hands, feet emphasis has produced a colossal reduction in fatal accidents.

The debate now is has it gone too far. My gut feel now is that I need to let those that are more qualified and removed to decide. And they are changing things in response to incidents and accidents. Thankfully they are ignoring the internet opinion.

But there is kick back from the pilot body. For instance the old USA method of dealing with stalls and wing drop is minimal height loss and use the rudder to lift the wing. They changed that after the airbus crash just after 9/11, its still getting taught and people are failing flight checks in the USA for not doing it.

 

[Alistair_Heaton]

https://avherald.com/h?article=503c63e9&opt=0

On Feb 6th 2023 Nepal's AIC reported that both flight data and cockpit voice recorders were successfully read out in Singapore. According to first analysis of the flight data recorders both propellers of the aircraft went into the feather position. The reason for the feathering of both propellers is still being determined, human factors as well as technical factors are still under investigation.

 

[Alistair_Heaton]

being lazy here just so i don't have go looking for the cockpit setup file.

 

[Alistair_Heaton]

The levers I have circled in red are called condition levers and control the props rpm and also feathering. The red things on top are part of the fire warning system and are mean to ensure you don't shut down the wrong engine.

The person flying wouldn't normally touch the condition levers. And they have a waggly shape on top so you tactically wouldn't confuse them with the power levers.

Just going to put in links to anything I find on ATR's a feathering engines.

https://flightsafety.org/asw-article/spurious-autofeather/

 

[RobWard]

Out of interest - how much feathering do the crew do? Do you normally just call for an amount of thrust and the engines sort out pitch and RPM, or is it something that you constantly adjust?

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

 

[Alistair_Heaton]

We only ever feather the engine in flight if its failed. Unless we are doing technical flight test which the majority of pilots will never do. So it would just be in the sim.

Feathering is the change of the prop blade angle so that its streamlined 89 degs and not producing drag. It can also not put any power into the airflow. The feathering selection manually also cuts off the fuel and the hydraulics to the engine on most types including this one.

Auto feather senses an engine failure and automatically moves the prop to 89 degs (normally its around 5-20degs). This is to give more performance by decreasing the drag on the failed engine. The crew then has to secure the engine which cuts off the fuel and hydraulics.

On the Q400 the fadecs spoke to each other so in theory it wouldn't autofeather both engines to keep electrical and hydraulic services available. Which some of us used in the simulator so wee didn't have to manually pump the gear down or flaps out for dual engine failure drills. The ATR72-500 has also FEDEC controlled engines but I don't know how its set up.

https://www.avweb.com/ownership/constant-speed-props/

http://www.pilotfriend.com/training/flight_training/fxd_wing/props.htm

Depends on the type how much you have to be involved in the Engine RPM. SAAB2000 you have buttons no condition levers. Q400 you have levers but they were micro switched linked to the FADEC, Jetstream none fadec it was a physical link to the prop pitch governor and you fiddled with them constantly to sync the blades to stop a interference beat. Looking at that photo the ATR has an AUTO setting for the RPM so they wouldn't normally touch them if I am correct in my thinking.

Power on a turbo prop is torque x rpm. Generally you would takeoff in max rpm which would give you max power then bring the rpm back to cruise and vary the power with the power lever. Then on finals you would increase the rpm to max to give you access to max power if required in case of a go-around.

 

[RobWard]

Ahh.. I thought feathering referred to all blade angle adjustments. I was thinking about a marine discussion somewhere on here where they would use variable pitch props (should I call them "screws"?) and they could get bogged down, so they'd lessen the pitch angle to accelerate the engine to peak power and then bring the pitch back to increase thrust. Is this essentially what you're doing on final in a turbo prop - keeping the engine at max power but controlling thrust with the blade angle?

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams