[Rahul Bhalgat]

Originally Posted by vinayrathore

Recently, I observed few weird patterns (would like to call them so as not aware what to make out). Every few days, one passenger plane takes off from the BIAL, hovers above HAL airport in Bangalore for close to 3-4 hours on average and lands back at BIAL. Since I live in the flight path of these hovers, I can vouch for the data on the app v/s what was there in reality. I have few screenshots too that show various Aircraft parameters including their registration numbers/Airlines etc. and their flight path. This activity always starts around 8 to 9 pm and end around 12 to 1 am in the night. The planes would just keep on hovering making U turns between Malur and Chikka Thirupathi on the east and around Koramangala in the west. The flight data shows starting airport as Bangalore but does not show destination and keeps hovering around FL45 to FL60. Its not the same airline always. Not posting the screenshots as not sure how safe it is to do so.

Observed around 6 to 7 such events in the past 2 months or so. Has anybody else observed it? What could it be?

One possibility: Maybe it is happening because some tracking system / ground instrumentation is being tested and that is why the plane needs to hover around a specific ground location at a specific altitude.

[Rahul Bhalgat]

Originally Posted by TKMCE

An airline crew (Jet Airways) reportedly manage to make it on the seventth and last possible landing attempt at Trivandrum , 3 of them at the original destination Kochi after exhausting all it fuel.

Soon after the Jet Airways incident, another airline (Air Asia India) diverted to HAL airport at Bangalore again citing fuel emergency.

And what has really happened to that blind landing and consequent damage at Jaipur of the Air India A320 Guwahati Delhi flight after yet another fuel emergency nearly an year back?

Another report on an Air India Express incident on a flght enroute to Pune again showed that it was not eactly caused by "circumstances beyond your control".

Are we all waiting for something major to happen before India's airlines gets it act together?. As a passenger, I sincerely hope not.

Hi TKMCE,

I appreciate your concern.

One common thing between Air India Express and Jet Airways is the ageing fleet. Possibly the air crafts involved in the above mentioned fuel emergency were old.

I think that no pilots would take off without adequate fuel quantity as per the guidelines. We can understand if the fuel emergency was because of weather or unforeseen extra detour. But if it was because of higher fuel consumption by the engine or due to faulty fuel gauge instruments, it is a thing to worry. If you know, please throw some light on the causes of these incidents.

Regarding the Air India Express incident on a flight enroute to Pune, what had exactly happened?

[RVD]

Originally Posted by Rahul Bhalgat

Hi TKMCE,

I appreciate your concern.

One common thing between Air India Express and Jet Airways is the ageing fleet. Possibly the air crafts involved in the above mentioned fuel emergency were old.

I think that no pilots would take off without adequate fuel quantity as per the guidelines. We can understand if the fuel emergency was because of weather or unforeseen extra detour. But if it was because of higher fuel consumption by the engine or due to faulty fuel gauge instruments, it is a thing to worry. If you know, please throw some light on the causes of these incidents.

Regarding the Air India Express incident on a flight enroute to Pune, what had exactly happened?

Firstly, Jet airways does not have an aging fleet. Its average fleet age is ~4 years. This is nothing compared to the average fleet age of many legacy careers in the west.

The diversion was due to weather only. What makes you suggest that it was due to excess fuel consumption by the aircraft? The engeenering department of an airline calculates something called as a" bias factor "for each aircraft on a regular basis. As the engine/ Airframe ages, its fuel consumption changes from that mentioned by the manufacturer. Hence Engeeniering does a fuel monitoring and comes up with a Bias value for EVERY aircraft in the fleet. The fuel for each sector is taken keeping in mind the Bias factor. Hence two aircrafts departing to the same destination may have marginally different fuel requirement. No aircraft ever departs without taking enough fuel considering all possible variables.

RVD

[Rahul Bhalgat]

Originally Posted by RVD

Firstly, Jet airways does not have an aging fleet. Its average fleet age is ~4 years. This is nothing compared to the average fleet age of many legacy careers in the west.

The diversion was due to weather only. What makes you suggest that it was due to excess fuel consumption by the aircraft? The engeenering department of an airline calculates something called as a" bias factor "for each aircraft on a regular basis. As the engine/ Airframe ages, its fuel consumption changes from that mentioned by the manufacturer. Hence Engeeniering does a fuel monitoring and comes up with a Bias value for EVERY aircraft in the fleet. The fuel for each sector is taken keeping in mind the Bias factor. Hence two aircrafts departing to the same destination may have marginally different fuel requirement. No aircraft ever departs without taking enough fuel considering all possible variables.

RVD

Bias factor is a new information for me. Thanks for the same.

I have not SUGGESTED that it WAS due to excessive fuel consumption by the air craft. I have only considered possible reasons. An engine may consume fuel at an excessive rate if there is something wrong.

When I book the flight, I filter the search results to eliminate Air India but Jet Airways has been acceptable to me. But my experience so far with Jet Airways is they had older air crafts, noticeably older when after you travel with Indigo and Go air. I have mostly done Pune - Delhi, Mumbai - Delhi and Pune - Ahmedabad.

I do not want to bash Jet Airways. I respect the foresight and professionalism shown by the Jet Airways founder. It is not easy to sustain in this business and he has done this.

[RVD]

Originally Posted by Rahul Bhalgat

Bias factor is a new information for me. Thanks for the same.

I have not SUGGESTED that it WAS due to excessive fuel consumption by the air craft. I have only considered possible reasons. An engine may consume fuel at an excessive rate if there is something wrong.

When I book the flight, I filter the search results to eliminate Air India but Jet Airways has been acceptable to me. But my experience so far with Jet Airways is they had older air crafts, noticeably older when after you travel with Indigo and Go air. I have mostly done Pune - Delhi, Mumbai - Delhi and Pune - Ahmedabad.

I do not want to bash Jet Airways. I respect the foresight and professionalism shown by the Jet Airways founder. It is not easy to sustain in this business and he has done this.

Indigo and Go Air do have newer aircrafts. Remember, they are much newer carriers compared to Jet airways. Though, Jet is also constantly bringing in newer planes as and when the lease of the older ones expire.

Regarding fuel consumption- except in case of a system faliure, all possible scenarios are catered for like engine/airframe age, weather at destination and enroute, traffic congestion at the destination airport to name a few. There are a few flight planning softwares in the market which are used by more or less all airlines in the world.

RVD

[Jeroen]

There is a misconception that new aircraft are safer then older aircraft. They are not, it is all down to how well they are maintained. A poorly maintained few year old jet could be a whole lot more unsafe then a properly maintained twenty year old jet.

This goes up to certain point, according to this study 27 years!

http://www.awg.aero/assets/docs/analysisofimpact.pdf

[apachelongbow]

To add on to the point, for your information, the turbo fan engines (jet) on each wing is interchangeable. Sometimes airlines add new engines to older airframes or a new airframe can carry an older engine. Apart from maintenance engineers, no one can make out the difference. Fuel burn increases with older engines, older airframes or change of paint/livery even. However the airlines operate on average fuel burn per hour and not fuel burn per each aircraft. And based on average fuel burn, the fuel on board for each trip is decided. Fuel planning is an exact science and is done by computerized trip planning, each day for each flight, based on weather forecasts, expected airspace/airport closure/availability, planned routing, expected changes due ATC, time of the day etc. There is enough fuel to cater for taxi, departure, climb, cruise, descent, approach, landing, and then enough fuel to divert to planned diversion airport if need be, with 30 mins of holding at planned alternate. Hence if a pilot runs out of fuel it will most likely be because of some emergency.

[Jeroen]

A long but quite interesting article on AF447 with a lot of background information on CRM anf flight automation. Still makes for a chilling read!

http://www.vanityfair.com/news/busin...ight-447-crash

[mohammedismail]

Emirates A380 which was heading to London from Dubai did Emergency Landing due to Landing Gear failure and the Boy Lord Aleem is not really happy with the way Emirates handled this situation.

https://www.youtube.com/watch?v=VqJnvTRGuqI

Here is the News LINK

[Enobarbus]

It is a scary situation for the ordinary passenger. However, the landing gear not retracting is not such a dangerous situation as the landing gear not extending. The news report's excessive criticism of the A380's landing gear problems is not justified in my opinion. In all probability, it is a minor glitch in a micro switch or a proximity sensor that lead to the failure. Occasional failures were reported in many systems of many aircraft. I am sure the reliability and maintainability data collectors would be working overtime to collate the relevant data, which will eventually lead to improvements to the system.
The A380's (as all other Airbus Aircraft's) landing gear is made by the Arle Court division of Smiths Aerospace UK. They are the makers of some of the most reliable landing gear systems (and other hydraulic and mechanical components) in the world and I would trust my life with their products any day. Smiths Aerospace was taken over by GE Aviation in 2007-08, but recently they hived off the Arle Court unit to Triumph Vought Aerospace (GE still retains the Avionics and Instrumentation units in Bishops Cleeve). Despite the changes in ownership, I heard that most of the older staff continue with the Arle court unit.
The A380 landing gear system has some of the most uniquely designed actuators to cater to the special needs of this behemoth. I had the good fortune to write the maintenance manuals for these components. I thoroughly enjoyed working on this project.

[searchingheaven]

I had the opportunity to use an A320 Simulator recently. The flight was uneventful, flying at 0.78 mach at FL300, in managed mode with a CORoute in the MCDU. There were a couple of problems though. The LVR CLB warning wouldn't go off even after reducing thrust lever to CLB detent. Also the FAULT light in BLUE Elect pump was popping up every now and then with warnings issued in the UPPER ECAM page as well.

As far as I understand, the fault light comes on if the reservoir level is low, or the reservoir overheats. Or the pump is delivering low pressure or is overheating. Same if the Reservoir Air Pressure is low. But I checked for all of these 5 parameters in the ECAM HYD page but couldn't find anything amiss.

Why was this happening? Can any pilot enlighten me on this?

[Jeroen]

Originally Posted by searchingheaven

Why was this happening? Can any pilot enlighten me on this?

We have a few Airbus drivers on the forum, I’m not one of them, but I do have some Airbus documentation. This is what the Instructor manual says:

QUOTE
Usually THR RED ALT = ACCEL ALT; it is defaulted to 1500 ft AGL in FMS but modifiable by the pilot as required by
the procedure (e.g. noise abatement).
Reaching THR RED ALT, LVR CLB comes up on FMA; bring the thrust levers back into CLB detent.
• Note that if FLX TEMP is very high, FLX N1 (EPR) is close to CLB N1 (EPR) but never below.
• When THR LVRs are set in CLB detent, ATHR is ON. If SRS mode is still engaged, the FD pitch bar will order a pitch down depending upon the amount of thrust decrease in between TOGA or FLX TO and CLB thrust.
When handflying, follow the pitch down order.
Reaching the ACCEL ALT, the target speed is set automatically to initial climb speed.
• Note that there is a significant pitch down order on the FD bar.
• Retract Flaps when IAS ≥ F with a positive speed trend.
• Retract Slats when IAS ≥ S with a positive speed trend.
• On A321, if the Take-off is achieved at high GW, S speed is above VFECONF1+F. In that case:
- accelerate towards S; at 210 kts the Flap autoretraction system retracts the Flaps to 0 and VFE on PFD goes to VFECONF1 230 kts.
In that case, should the IAS drop back below 210 kts, flaps will not extend back to 1 + F.
NOTE:
If the FCU ALT is low, ALT* will engage rapidly after lift off, before the A/C reaches THR RED or ACCEL ALT. In that case, LVR CLB comes up on FMA and target speed goes to initial climb speed.
The same will happen if the pilot manually pulls OPEN CLB or V/S.
In many cases, THR RED ALT = ACCEL ALT. Thus the LVR CLB message comes up simultaneously on the FMA with CLB (OPCLB) mode, and target speed increases. In that case, when hand flying the aircraft, follow the FD pitch down order first, and then set THR LVRs into CLB detent.
UNQUOTE

Did you pitch down?

Jeroen


[searchingheaven]

Originally Posted by Jeroen

We have a few Airbus drivers on the forum, I’m not one of them, but I do have some Airbus documentation. This is what the Instructor manual says:

If the FCU ALT is low, ALT* will engage rapidly after lift off, before the A/C reaches THR RED or ACCEL ALT. In that case, LVR CLB comes up on FMA and target speed goes to initial climb speed.
The same will happen if the pilot manually pulls OPEN CLB or V/S.
In many cases, THR RED ALT = ACCEL ALT. Thus the LVR CLB message comes up simultaneously on the FMA with CLB (OPCLB) mode, and target speed increases. In that case, when hand flying the aircraft, follow the FD pitch down order first, and then set THR LVRs into CLB detent.
UNQUOTE

Did you pitch down?

Jeroen


I was handflying the aircraft. I don't remember pitching down since I was climbing to the THR RED Altitude, set at 2100 ft in the MCDU manually by me. I climbed to 2100ft, at that point my AOA must have been in the range of 13 degrees to 17 degrees. Then I reduced the thrust lever to climb detent. But the LVR CLB kept flashing till about FL140.

I think this is what must have happened. The manual states a pitch down level off manoeuvre and then thrust reduction. I didn't follow that order I guess.

[Jeroen]

Originally Posted by searchingheaven

I was handflying the aircraft. I don't remember pitching down since I was climbing to the THR RED Altitude, set at 2100 ft in the MCDU manually by me. I climbed to 2100ft, at that point my AOA must have been in the range of 13 degrees to 17 degrees. Then I reduced the thrust lever to climb detent. But the LVR CLB kept flashing till about FL140.



I think this is what must have happened. The manual states a pitch down level off manoeuvre and then thrust reduction. I didn't follow that order I guess.

Just out of interest, where, what simulator did you get to fly?
Jeroen

[searchingheaven]

Originally Posted by Jeroen

Just out of interest, where, what simulator did you get to fly?
Jeroen

It was at FSTC Delhi, for a duration of about 55 mins. But there was only a 10 min debriefing and no debriefing. Hence the questions. The details of the simulator are attached below.