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Old 25th February 2019, 09:09   #121
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Re: Airbus A320neo: Pratt & Whitney engine issues

Aircraft calculate their own weight after takeoff from angle of attack sensors, if there is a gross mismatch from weight/data input by pilots and sensed weight an error is thrown.
Cameras are silly, lens can fog up, parallex erros can crop up, not fool proof, a pelothra of sensors which are rubost do the job much better, that's why always trust your instruments, will you rather have a camera showing you the engine bay in your car or a sensor/s which show the malfunction via a management computer and a light/error code??
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Old 25th February 2019, 10:18   #122
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Re: Airbus A320neo: Pratt & Whitney engine issues

Quote:
Originally Posted by AirbusCapt View Post
Aircraft calculate their own weight after takeoff from angle of attack sensors, if there is a gross mismatch from weight/data input by pilots and sensed weight an error is thrown.
Cameras are silly, lens can fog up, parallex erros can crop up, not fool proof, a pelothra of sensors which are rubost do the job much better, that's why always trust your instruments, will you rather have a camera showing you the engine bay in your car or a sensor/s which show the malfunction via a management computer and a light/error code??
The reference here is with inflight accidents where pilots were unable to see what had happened e.g. NorthWest Flight 85 and so many others. The discussion was not on using cameras to fly. That I agree with you will be utterly impractical.
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Old 25th February 2019, 11:25   #123
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Re: Airbus A320neo: Pratt & Whitney engine issues

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Originally Posted by V.Narayan View Post
The reference here is with inflight accidents where pilots were unable to see what had happened e.g. NorthWest Flight 85 and so many others. The discussion was not on using cameras to fly. That I agree with you will be utterly impractical.
Sir, in the northwest85 case, there was no way of viewing metal fatigue/crack except with a boroscope. I doubt if a camera would help. Regarding uncommanded rudder deflection, at least Airbus gives you the view of the rudder and travel limit position on a schematic page under flight control, in real time. All flight control surfaces, engines, landing gear, and most other important things have atleast 2/3 sensors picking up signals and transmitting in real-time to the crew. Even a trained crew cannot visually observe say an aileron position in flight and say if it is normal or abnormal, sensors and computers do it flawlessly.
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Old 25th February 2019, 12:58   #124
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Re: Airbus A320neo: Pratt & Whitney engine issues

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Originally Posted by AirbusCapt View Post
Aircraft calculate their own weight after takeoff from angle of attack sensors, if there is a gross mismatch from weight/data input by pilots and sensed weight an error is thrown.
How do you calculate the aircraft weight from an angle of attack? Please explain. In order to calculate the angle of attack at a given airspeed and air density you need weight (and some more stuff). Doing it the other way doesn't make sense to me. You need to figure out how much you weigh on the ramp, still parked. To much depends on weight!

The most important part of the weight is related to actually taking off. Your weight (plus a few other parameters) determines your take off power settings, your V1 and Vr, V2. Also it determines if you have enough runway to do an actual take off and still stop in you abort at or prior V1.

In addition weight is absolutely required for your weight and balance calculation. You need to determine the center of gravity, ensure that is within limits (if not move fuel, pax and or cargo) and dial in the appropriate trim (where applicable) prior to take off.

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Old 25th February 2019, 14:07   #125
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Re: Airbus A320neo: Pratt & Whitney engine issues

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Originally Posted by AirbusCapt View Post
Sir, in the northwest85 case, there was no way of viewing metal fatigue/crack except with a boroscope. I doubt if a camera would help.
Talking of the fact that for quite sometime the flight crew did not know that part of the aircraft was 'missing'.

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Old 25th February 2019, 15:22   #126
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Re: Airbus A320neo: Pratt & Whitney engine issues

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Originally Posted by Sutripta View Post
Talking of the fact that for quite sometime the flight crew did not know that part of the aircraft was 'missing'.
What would the pilots have done differently? Rudder deflection is shown in the cockpit on a 747 and the pilots noticed that too. And took appropriate action.

The incident happened at 5.40PM Alaska Daylight time in October. So they were already flying in the dark. Cameras are of no use in the dark. Jeroen

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Old 25th February 2019, 15:30   #127
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Re: Airbus A320neo: Pratt & Whitney engine issues

Quote:
Originally Posted by Sutripta View Post
Talking of the fact that for quite sometime the flight crew did not know that part of the aircraft was 'missing'.
I don't know SOP but I'm surprised the cabin crew did not inform the pilots about what happened. (the video doesn't detail it out, hence the assumption)

When the aircraft suffers an incident that risks its ability to fly safely, and the cabin crew can see what and how, wouldn't they want to tell the pilots so they know the aircraft's limitations?
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Old 25th February 2019, 15:38   #128
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Re: Airbus A320neo: Pratt & Whitney engine issues

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Originally Posted by Jeroen View Post
What would the pilots have done differently?

The incident happened at 5.40PM Alaska Daylight time in October. So they were already flying in the dark. Cameras are of no use in the dark. Jeroen

Jeroen
Situational awareness. And reported correctly to ground control.

Camera sensor spectral sensitivity does not need to follow that of human eye!

It is almost as if you expect the inclusion of a video feed to be harmful. What harm?

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Last edited by Sutripta : 25th February 2019 at 15:41.
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Old 25th February 2019, 15:47   #129
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Re: Airbus A320neo: Pratt & Whitney engine issues

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Originally Posted by libranof1987 View Post
I don't know SOP but I'm surprised the cabin crew did not inform the pilots about what happened. (the video doesn't detail it out, hence the assumption)

When the aircraft suffers an incident that risks its ability to fly safely, and the cabin crew can see what and how, wouldn't they want to tell the pilots so they know the aircraft's limitations?
There was nothing you could see from the cabin. This was the (lower) rudder and it was most likely dark as well. Even in full day light you can not see the tail of an aircraft from the cabin.

If cabin crew does see something they think is amiss, they most certainly will tell the cockpit.

Quote:
Originally Posted by Sutripta View Post
Situational awareness. And reported correctly to ground control.

Camera sensor spectral sensitivity does not need to follow that of human eye!
Maybe, but they actually figured out quite quickly what was going on, more importantly how to get the plane under control. Not sure what visuals clue would have added. They would still have to follow the same procedure.

This was initially a 17o deflection of the lower rudder. That is not much and it would be hard to pick it up on camera, any type. Picking up details from cameras is not that straight forward as it seems. Only when something big is way out of whack would you pick it up.

Somehow the aviation industry never picked up on it. To cumbersome, not practical etc. I am not expert in this field, but I do not think anybody was ever convinced it would add additional safety. Except maybe for some very odd cases.
Adding cameras to the cabin and cockpit is something that has been debated for some years and it is slowly taking hold to some extent. It's a little easier seeing how that would add to the overall safety

I have read about a camera system that looks at the main gear upon touch down. It supposedly is able to quicker detect smoke (tyre, brake) then conventional means.

There are also image enhancing type of cameras that will give you better visibility in rain, snow, fog etc type of condition. Some of the little planes I fly already have these incorporated

Jeroen

Last edited by Jeroen : 25th February 2019 at 15:54.
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Old 25th February 2019, 15:59   #130
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Re: Airbus A320neo: Pratt & Whitney engine issues

Quote:
Originally Posted by Jeroen View Post
If cabin crew does see something they think is amiss, they most certainly will tell the cockpit.
We might be talking of two different accidents.

In my post, I am referring to the one Mr. Narayan mentioned:

Quote:
Originally Posted by V.Narayan View Post
A well made video by Flight Channel, on Southwest 1380, explaining what happened and the handling by the 2 pilots.
Quote:
Originally Posted by Sutripta View Post
Always wondered about a number of things:
A) Why no cameras (with feed to cockpit) to give better situational awareness for pilots.
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Old 25th February 2019, 16:35   #131
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Re: Airbus A320neo: Pratt & Whitney engine issues

Quote:
Originally Posted by libranof1987 View Post
We might be talking of two different accidents.

In my post, I am referring to the one Mr. Narayan mentioned:
Ah Yes I see.
I am not sure what the cabin crew could tell the pilots they would not know in the cockpit. They know they had a massive engine failure and a cabin depressurization.

What could the cabin crew tell the pilots that was relevant and would have made them do anything differently?

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Old 4th April 2019, 21:02   #132
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Re: Airbus A320neo: Pratt & Whitney engine issues

In light of the recent 737 Max crashes, there is some criticism of the lack of technical expertise of the DGCA:
http://www.moneycontrol.com/news/bus...-3755161.html/

To us lay persons the article seems credible but it works be good to hear from better informed team bhp members.

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Old 4th April 2019, 21:11   #133
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Re: Airbus A320neo: Pratt & Whitney engine issues

Quote:
Originally Posted by Motard_Blr View Post
In light of the recent 737 Max crashes, there is some criticism of the lack of technical expertise of the DGCA:
http://www.moneycontrol.com/news/bus...-3755161.html/
To us lay persons the article seems credible but it works be good to hear from better informed team bhp members.
The link goes to the home page of the news website and not to the article you are referring to.
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Old 5th April 2019, 07:18   #134
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Re: Airbus A320neo: Pratt & Whitney engine issues

Quote:
Originally Posted by V.Narayan View Post
The link goes to the home page of the news website and not to the article you are referring to.
Must be a broken link. Here is the text of the article:

Quote:
Is DGCA going easy on Airbus A 320 Neo despite repeated engine failures? Experts think so
DGCA had temporarily grounded Airbus A 320 Neos in early 2018, which was gradually lifted after Airbus and P&W assured of restoring the issues
Nikita Vashisht

On April 2, 2019, budget carrier IndiGo reported a mid-air engine failure on one of its flights. This was the sixth such incident in a span of two weeks involving its Airbus A 320 Neo fleet.

This was the 13th incident since January this year where this class of aircraft, mainly used flown by Indigo Airlines and Go Air, have reported problems including mid-air engine failures and mid-air turn backs.

The aircraft, powered by Pratt and Whitney (PW-1100) engine, have faced operational and technical glitches since 2017, prompting questions on why the regulator Directorate General of Civil Aviation (DGCA) is not more stringent on such glitches that involves passenger safety.

Sector experts that Moneycontrol spoke to believe it’s time the watchdog ups its ante and “gain some technical expertise” before giving clearance to faulty engines.

Ethiopian Airlines pilots initially followed Boeing procedures before crash: Report
“Regulators are at the crux of the problem. They blame airlines and pilots and others that they didn’t provide sufficient data or didn’t do safety check but are they, themselves, competent enough to determine what is wrong with the aircraft or may be what could go wrong,” Mark Martin, chief executive officer, Martin consultancy, told Moneycontrol.

At crux of the problem is PW-1100 engine by P&W which are used in A 320 Neo aircraft by France-based plane making giant Airbus. The fleet first reported engine failure in 2017 and has since faced several issues.

“The problem is that Indian DGCA doesn’t have the technical competence to evaluate the engine of the aircraft. The previous manpower kept on retiring and they have not been able to replace those people who can evaluate it,” Harsh Vardhan, an aviation expert told Moneycontrol.

“DGCA usually keeps non-technical people who are never able to understand the intricacies of it,” he said.

DGCA had temporarily grounded A320 Neos in early 2018, which was gradually lifted after Airbus and P&W assured of fixing the problems. A year later, in January 2019, DGCA further issued directives for IndiGo and GoAir to have “weekly inspection” of the engines “as per P&W special directions” and “train staff to identify foul smell” in the aircraft.

It imposed restriction on longer duration flights, especially to Port Blair” to avoid a situation where emergency landing can’t be done.

Despite this, A320 Neo continues to face engine related issues. Recent incidents include:
Airline Date Issue
IndiGo Apr 2, 2019 Mid-air failure, excessive engine vibration
IndiGo Apr 1, 2019 Mid-air failure, oil chips in engine
IndiGo Apr 1, 2019 Excessive vibration
IndiGo Mar 30, 2019 Mid-air engine failure
IndiGo Mar 21, 2019 Mid-air engine failure
GoAir Mar 24, 2019 Take off rejected twice due to power loss in engine
GoAir (G8 760) Mar 15, 2019 Mid-air engine failure, Engine 1 air bleed leakage, landed without dumping fuel
GoAir (G8 150) Mar 7, 2019 Mid-air engine failure, oil chips detected in engine, unusual heating, oil loss, oil leakage, bearing problem
GoAir Feb 6, 2019 Heavy vibration and mid-air failure
Indigo (6E 451) Jan 21, 2019 Heavy vibration and mid-air failure
GoAir (G8 319,) Jan 10, 2019 Mid-air failure and high vibration
IndiGo Jan 3, 2019 Loud bang, mid-air failure, smoke and vibration
IndiGo (6E-6373) Jan 1, 2019 Smoke in cockpit
IndiGo (6E 923) Dec 10, 2018 Engine blades burned out and heavy smoke
IndiGo (6E 6616) Dec 23, 2018 Mid-air engine failure
IndiGo Nov 20, 2018 Mid-air engine failure flight
Indigo flight (6E 866)
Nov 2, 2018

Engine failure after heavy vibration
GoAir (G8 423) Oct 26, 2018 High/excessive vibration in engines
Two GoAir flights Oct 20, 2018 Engine failure and smoke warning in cargo
GoAir (G8 033) Oct 20, 2018 Mid-air engine failure
GoAir Oct 20, 2018 smoke warning in cargo, Mid-air turn back
IndiGo (6E 452) October 8 Midair engine failure, gearbox disintegration, one engine goes dead
IndiGo Sept 10, 2018 Oil chips detected in engine
IndiGo (72 aircraft) and GoAir (30 aircraft) are the only two operators that use A320 Neo series planes in India. Both the airlines declined to comment on the story.

“It has been going on for year and a half… It’s not a one-time issue,” Vardhan said, adding, “The problem of in-flight shut down is a serious issue, especially for those aircrafts that have both P&W engines. It is a safety risk… They shouldn’t wait for a B737 Max-like situation to arrive”.

Vardhan was referring to grounding of Boeing manufactured 737 max series planes which were involved in two fatal accidents within a span of six months, killing over 300 passengers.

Sources said that while initial engine faults were resolved in a couple of months of operation, airlines later reported issues related to Number 3 lift of seal, combustor issues and knife edge seal.

A P&W spokesperson told Moneycontrol that steps have been by the company to resolve the issues and that 95 percent of the aircraft have been retrofitted with resolved engines.

“Remaining five percent will be done by first half of 2019,” he said.

In a written response to Moneycontrol, Airbus said that the P&W fleet “continued to meet all airworthiness criteria for safe flight (incl. ETOPS 180)” and that “root causes for disruptions and implications were understood and latest modifications (were being) performed (for) successful flight testing”.

“Fulfilling a regulator’s criteria means absolutely nothing for P&W because, in reality, they need to get down and sort the problem. They should do a complete replacement, which they aren’t doing due to cost constraint,” Martin said, adding “Even if the stakeholders say that the issues have been resolved, we need to ask why the metal is cracking in the first place. And does titanium crack? How can you justify metal fatigue on brand new engine?”

“I don’t think Airbus and P&W have done enough as the problems continue to persist. Its time they go back to basic designing and check for flaws,” Vardhan said.

Time for DGCA to go independent?

Experts opine that India operates in “extreme weather conditions,” which calls for independent decision taking with respect to clearance certification.

“India, unlike other countries, has the most varied style of operating due to extreme climate conditions. There are all kinds of climates, including high temperatures, sea shore area, hills, high mountains and rainfall. So DGCA must have a much more extensive technical role, which can check the aircraft for all these conditions,” Vardhan explained.

He further added that after the B737 Max incident, regulators across the globe should not blindly follow benchmarks set by US based Federal Aviation Administration (FAA) and EU based European Union Aviation Safety Agency (EASA) for giving out clearance certificates.

During the entire episode, FAA had intially continued to endorse statements by Boeing and had refused to ground B737 planes even as more than 50 countries barred the plane from flying in, out and over its airspace. After pressure mounted on Boeing and it agreed to ground the plane, FAA ordered “emergency grounding” of the crisis hit plane.

“The process of certification for an aircraft in India is based on FAA and EASA. Once they give the clearance, DGCA considers it to the benchmark, endorses it and gives clearance anyway. They usually do only limited checks… Only when you have a very strong reason, you are able to oppose them. Something like that happened with B737. It was like a rebellion when other counties first grounded it and then FAA agreed to do so,” Vardhan said, who added that the rating agencies or the approval agencies “must be more careful” and “shouldn’t rely on FAA or EASA certification”.

“Countries, including India, must take independent decisions and that’s what DGCA must be doing. We have seen that FAA was kind of listening to Boeing who also obtained the clearance for the aircraft by watering down things (safety norms),” he said.

EASA, in early 2018, had ordered Emergency Airworthiness Directive (EAD) for A320 Neo series planes.

“Several occurrences of engine in-flight shut-down (IFSD) and Rejected Take-Off (RTO) have been reported on certain Airbus A320neo family aeroplanes. While investigation is ongoing to determine the root cause, preliminary findings indicate that the affected engines, which have high pressure compressor aft hub modification embodied from ESN P770450, are more susceptible to IFSD. This condition, if not corrected, could lead to dual engine IFSD. To address this potentially unsafe condition, Airbus issued Alert Operators Transmission (AOT) A71N014-18, providing instructions to de-pair the affected engines and discontinue Extended range Two-engine aeroplanes Operations (ETOPS) for aircraft fitted with affected engines. For the reasons described above, this AD requires implementation of operational restrictions. This AD is considered to be an interim action and further AD action may follow,” it said in its statement.

While DGCA did not respond to queries sent by Moneycontrol, Airbus said that overall in-service P&W fleet performance “continued to improve significantly and demonstrates high level of operational reliability of 99.6 percent with trend going towards 99.7 percent. A P&W spokesperson said that “safety was non-negotiable” for the company.

Martin, however, questioned the quality of metal and equipment being used for manufacturing the airplanes and engines.

“In 2005, the Manmohan Singh government brought an anti-dumping policy, which said that technology and equipment not accepted in the world will not be brought to India and sold (here) just because we are a buyers’ market… We had an Anti-dumping Act,” he said, adding, “Make in India was surely a circumvention for anti-dumping. The Modi government's Make in India in aerospace has led to dumping of foul category of goods in India, which is being sold off after being ‘manufactured’. Are you telling me that the metal which was not accepted in the world is being dumped in India as (raw material) for engine manufacture?”

Way forward?

The way out of this situation could only be thorough inspection of affected engines and their complete replacement, experts said.

“DGCA has the authority to inspect these engines and see where the performance is lacking. However, in these situations where in-flight shut downs are taking place, either DGCA should withdraw their (approval) certification or impose certain conditions for their operation, like making it mandatory to have one CFM engine in case of two-engine aircraft,” Vardhan said.

Martin said that Airbus must not think about cost and should stop using P&W engines.

“A320 Neo has two engine options (CFM and P&W). Why doesn’t Airbus recommend both engines to be CFM? Why do we have to go back to P&W? The reason is the other engine is 45 percent costlier,” he said.

While P&W had to pay compensation to IndiGo and GoAir for all the grounded planes, Martin said that the company should rather use better quality material instead of giving compensation.

“Is the compensation any cheaper than better quality raw material?” he questioned.

Last edited by SmartCat : 5th April 2019 at 20:02. Reason: Removed unrelated content
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Old 12th April 2019, 20:44   #135
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Re: Airbus A320neo: Pratt & Whitney engine issues

Has P&W found any solution to this mess? Why does Indigo still continue adding new A320Neos with P&W engines? They could switch their new A321neos over to CFM engines. Why are they not doing that?
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