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Does anybody has knownledge about Rolls Royce's Direct Accumulation Counts (DACs) for LLP's Calculation for RB211-535E4?

I am recommending very slowly.

by anyonous (guest), 05 Sep 2018 22:22
woon bon (guest) 23 Aug 2018 09:58
in discussion Pilots / General Aviation pilots (INCIDENTS) » GA INCIDENTS (general discussion)

how do i become an airline

by woon bon (guest), 23 Aug 2018 09:58

I am working as a B1 certifying engineer in an Airline , the way of controlling the maintenance personal duty hours and to prevent stress of working extra hours is simple but no airline I believed is doing it , the simple method is to make the rules of duty hours and make a personal log book for each maintenance staff should be signed by the staff and shift leader / supervisor and this book to be submitted to the authorities ( quality control section - the civil aviation authorities ) to make sure that no one exceeds the duty limitation monthly .
That is it

How we can turn IP shaft in Trent 1000 engine for bore scope inspection ?

In every case of such situation, there are human errors. Not only the appropriate statistic is enough, was this deciphered from the black box?I usually do some reports about this, but from time to time.

I would recommend checking some online learning platforms, such as,, udemy etc. They offer courses on a variety of topics, such as engineering and industrial subjects. They might have some useful course on drawings or designing of aircrafts as well.

by industrialmanliftsindustrialmanlifts, 16 Dec 2016 11:18


I have just read your email. Probably at this time you have made your decission.

Your diploma in A/C maintenance Engineering should be also applicable to work in modifications to the certified design ( called Type Design or Supplemental Type Design STC _ you may check FAA and EASA sites for more information). Within this field, you may dedicate to aircraft interiors design. As an engineer you will be not only able to draw a nice artistic concept but ALSO consider the technical complexities of the certification (ie Cabin Safety) , installation, testing and maintenance. There is a huge working area in Aircraft Interiors wnere creativity and artistic care are very appreciated. You may take a look on the site
Good luck and go ahead! Then I wish you Selamat Jalan……

Warm regards


by Juan (guest), 21 Apr 2016 08:18

Hi guys. Im a student from Malaysia. I really need help from your guys opinions.My family is not very rich, yet they managed to let me study this course.And to really say this, i dont think i like this course.I had a more creative mind.I like to draw alot. I wanted to change course but the problem is that im tied with this PTPTN, a form of borrowing money from goverment for studies.Im stuck with that.If i change course, i must repay back the depts which is around RM 10k and also first paid to the university RM11K.So, i will waste a total of RM21k. That is alot of money.So i decided that i finish this course,(diploma in aircraft maintenance engineering) and try to go for a degree that requires creativity or drawing , designing , related to aircraft, so I need your guys opinion, any degree programs that is related to drawings or designing of aircrafts??

what are the pay anr perks you guys recieve as a air traffic controllers

by annonym (guest), 04 Feb 2014 14:05

maintaining the maintainers? What impact has human factors research and intervention had on overall aircraft safety?

Myself and other Aircraft Engineers will agree the above statement is rubbish!

First, Licensed Aircraft Maintenance Engineers (LAME) fall under the demarcations set out by the local airworthiness authority and the rules within Part66 of CAA rules. Maintaining the maintainers? LAME's have a delegation authorized by the CAA to certify maintenance iaw the above rules within the boundary's of his/her ratings and category.
Those who do not reflect on history are distend to repeat it. Human Factors research has influenced the overall safety of aircraft operations and maintenance.

A better question to ask is, Without Human Factor Research and interventions within aviation, how would this effect overall aircraft safety? I assume in the essence of safety, the answer is reasonably clear.

by PalTechRepPalTechRep, 01 Oct 2013 09:40

maintaining the maintainers? What impact has human factors research and intervention had on overall aircraft safety?

by Grant Stewart (guest), 20 Sep 2012 04:09

In my experience duty time for personnel involved in maintenance has never quite been taken seriously. As you say we have come a long way in understanding the effects of fatigue, but the management of it seems to lie squarely on the shoulders of the individual and their ability to say 'no, I must adhere to duty times'. Duty times are put in place to support engineers' in ensuring that they can perform their job in a safe and effective manner and yet it is engineers' who choose to work outside duty times. So why do we seem to have the inability to follow the law? Is it a lack of understanding of why duty times exist? Company pressure? Financial reasons? Inadequate resources, i.e. manpower? The love of aircraft? In my opinion, a little of everything. Engineers have a special nature and take great pride in their work. When an aircraft goes tech they feel an overwhelming responsibility to get the aircraft back up and flying and prefer to see the job through to the end regardless how long this might take. Although their is a heirachy within the maintenance organisation engineers' tend to take control of their own working environment, meaning, they may be working an 8 hour shift, but if at the end of that shift they still have a broken aircraft they will decide themselves to stay or go. There is no single person to control duty times, if an engineer chooses to stay then the responsibility relies solely with him/her, and the company itself seems to follow the philosophy that an engineer has read the company procedures, they know the rules and they have chosen not to adhere, should anything happen. We are also very individualistic in nature in such that we do not function as a group, one engineer may say no to working outside duty times, but the next may not follow ensuring that there is always someone who is willing to work outside the scope.
Engineers' are taught about fatigue, told the effects, shown example of accidents caused by fatigue, and shown the law that governs allowable working hours, however without an effective fatigue management process which includes the monitoring of duty time engineers will continue to work outside the rules.

There have been many mid-air incidents and sadly, a couple of mid air accidents during my ab-initio days.
Personally, there have been 2 occasions that would have led to a disastrous ending if not managed well.

1. Back in 2006 when I was doing my VFR Navigation flight up North towards NZNP, I have planned to do a touch & go at NZWU on the way up. NZWU is not a controlled aerodrome in a MBZ. Weather information is available for NZWU through the AWIB. Therefore, the runway in use is determined by the pilot operating in the area.

As I approached NZWU, I got the weather and it was favoring the South facing Runway. I made my calls in the MBZ and heard nothing on the air so I just carried on my approach into NZWU as per planned. However, as I called overhead and joining left hand downwind for the approach, another aircraft called up and broadcasted that he was on the finals of the reciprocal runway for a touch and go before carrying on his journey down south. By then, I was already on the left hand downwind. I called for him to make a left hand turn upwind instead of his broadcasted intention to vacate via the right hand downwind (which was where I was coming in from). I did not get a response from him so I watched him as he did his touch and go. Hoping that he knew I was there from my broadcast and attempt to communicate with him, to my horror, he made a right turn and started heading towards me. I managed to space myself out on a wider downwind before carrying out my approach. When our aircrafts passed each other, it was near enough for me to see the shock on the pilot's face to see the proximity of our aircrafts.

A few things I learnt from this:
a. Airmanship - Always broadcast even when you think that no one is listening
b. Airmanship - Always use the runway the wind is favoring if it is an uncontrolled aerodrome. If you decide to otherwise, do broadcast your intentions
c. Communication - Listen out and not just broadcast for the sake of broadcasting.
d. Situational Awareness - Always know what the other pilot is doing and how it will affect you.

2. In 2007, I was returning from an IFR NAV on a Seneca into NZPM. We came in for Rwy 07 for the circling approach for Rwy 25. The circuit area then was active and there were about 2 other aircrafts in the circuit. I shot my approach down to 700' and broke right to circle left for Rwy 25 as requested by ATC. As I joined left hand downwind for 25, there was another single engined aircraft at 1100' ahead of me. Tower gave instructions to the other aircraft above us to make a right hand orbit at his position to allow us to land first since we were lower and will be faster than him. The pilot acknowledged the instruction of the ATC. However, as we continued to fly downwind, we saw that the guy did not make an orbit and instead, he started descending and turning left to join base for the approach. Immediately, we made a right turn and informed tower that we'll orbiting due to traffic closing in on us from above for the approach. Tower later made the pilot land for a full stop and we continued our approach after him.

Few lessons from here:
a. Communication - Always understand the instructions from ATC and not just read them back because it is the right thing to do
b. Situational Awareness - Always know where the other aircraft are even though you are under radar coverage
c. Situational Awareness - Always know what the instructions ATC gives you is about and not just follow blindly. ATC may have made a mistake or someone else flying or even yourself may have made a mistake.

Re: Ab-initio MID-AIR INCIDENTS by nchewnchew, 08 Nov 2011 14:37

It was one of my very first short-field takeoff trainings on Palmerston North Grass runway25. Grass runway at Palmerston North airport is very short, it is only about 600 metres long with a paved taxiway in the middle of it. The surface condition on the day was wet and soft as it had been closed for a while , however it was cleared safe to conduct a takeoff and landing on the day. On every takeoff, especially in a short-field takeoff a pilot is required to have a decision point where he/she decides whether to continue or abort the aircraft. This decision point during a short-field takeoff can be selected by selecting a point on the runway and the safe airspeed for the takeoff to be continued at the particular point. As the aircraft I flew on the say was PA-28, my decision point was at the paved taxi way at speed of at least 40 kt. I kept saying to myself that "I need to have at least 40kt passing the taxiway" This decision was shared to and agreed by flight instructor sitting next to me. I applied full power and the takeoff was commenced on a wet and soft Grass 25. As the aircraft was rolling, the airspeed did not increase as much as I expected from the past flight. It only increased slowly. As passing my decision point(taxiway), airspeed was still about 35kt. Without saying anything to the instructor, I decided the abort the takeoff, and quickly close the throttle to idle along gentle braking. The instructor was surprised by my sudden action, however he had no time to apply full-power again as the distance left to run was insufficient. He then helped me with more braking in order to stop the aircraft within the distance available as my braking alone was insufficient. The aircraft came to a fully stop within the grass distance, the nose wheel was sitting just at the end edge of the runway.

After the flight, I had a talk about my decision with the instructor. He mentioned that the decision was good, however it was very poor communication as I didn't say "ABORT!!!" and also insufficient braking applied when the decision was to abort. At least I should have told him my decision to abort before acting so. He also mentioned that if I had told him he would still be happy to continue the takeoff. And also when decide to abort the aircraft due to many reason, maximum braking should applied.

The big thing I learnt from this flight was that when aborting the takeoff maximum braking should be applied to stop aircraft within available distance. It was lucky that there was a flat grass surface after the Grass runway at Palmerston North. What if it was something else?? And also the effective communication between crew is always required, especially when flying with a flight instructor who is the Pilot in Command and has more experience in flying as at the time I only about 12 hours of experience.

Aborted Takeoff by Teerawit PulpinyoTeerawit Pulpinyo, 12 Sep 2011 11:41



Embedded as a customer within an overseas-based aviation contractor working on an aircraft avionics upgrade project, I observed and experienced multiple safety incidents related to standard operating procedures. Documented below are two examples which highlight the importance of following procedures, describe the consequences of not following procedures, and demonstrate poor communication within an aviation organisation. Arguably, these examples demonstrate defences preventing potential accidents.


During the flight testing program the aircraft was configured for a particular serial and dispatched by the contractor in preparation for flight. As a part of this standard procedure/process the contractor maintenance team was to brief the aircrew on the serviceability state of the aircraft (during the pre-flight brief). The brief included the following:

• Project installations which had occurred since previous flight,
• Maintenance and repair carried out on the aircraft since last flight,
• Long term acceptable defects to be carried on the flight,
• General servicing and replenishment information,
• And any other relevant information pertaining to maintenance on the aircraft.

On this occasion the brief was completed and it was announced that the aircraft was serviceable for flight. When aircrew pre-flight was complete the contractor produced its maintenance release form fully signed, the aircraft maintenance log book was signed and the aircraft was released for flight.

As the aircrew were strapping into their seat and the aircraft ladder was about to be lifted the contractor’s quality assurance lead wandered into my office and handed me some paperwork. The paperwork indicated that during the evening the nightshift maintenance team had carried out rectification on a long-term defect on the autopilot system. Further inspection of the paperwork suggested that after a re-wire of a connector in the autopilot system, no functional and independent functional had been carried out. These are standard maintenance procedures. The contractor who briefed the aircrew on maintenance made no reference to this autopilot work and in fact had no idea the work had been carried out over night by the other shift.

After a quick exchange of words with the contractor I immediately went out to the aircraft to explain to the captain that his flight was going to be delayed, and that he needed to sign the aircraft back to maintenance so the contractor could carry out the functionals prior to the aircraft flying. Of note, in 25 years of working in aviation maintenance it was the first time I had to prevent an aircraft from flying.

Potential Safety Implications

The safety implications of this maintenance error have the potential to be catastrophic. An example would be an incorrectly wired autopilot system has the potential to place the aircraft in an incorrect sense (attitude). A functional and independent function confirms the autopilot system operates in the correct sense.

Incident Cause

• Lack of adherence to standard operating procedures.
• Poor communication between the two functional elements in the contractor’s maintenance team.

Human Factors Lessons

It could be argued system defences captured this error prior to the aircraft taxiing but in reality it was a matter of timing which allowed this error to be picked up. Equally it could be argued if there was a problem on engaging the autopilot the pilot's skills, expertise and SOP's would mitigate the likelihood of an accident. However, if this maintenance error remained latent and lined up with other active and latent errors, and defences were breached, then a major accident could occur (Accident Causation Model).

Two important lessons can be derived from this incident:

• Standard operating procedures are an important element in a safety management system. Procedures are put in place to reduce error and mitigate consequences of error so they should be followed, and this ethos should be followed in all levels of the organisation.
• Communication is an important aspect of a safety management system. It allows information flow from top/down and bottom/up. The positive aspects of good communication contribute to safety and efficiency. In this case good communication between the maintenance shifts would have highlighted the functionals were not carried out and the customer would have been fully informed that the work had been completed.


During standard post-flight maintenance on the aircraft described in incident one, the contractor’s maintenance staff were required to follow the customer’s standard operating/maintenance procedures, and these were laid out in the form of work cards.

On this aircraft there are two hydraulically activated large doors on the underside of the aircraft. To make these doors safe there is a safety pin (locking device) which is inserted at all times on the ground which prevents the inadvertent or accidental actuation of the doors with the aircraft hydraulic systems powered on the ground.

In short on two occasions this procedure was not followed correctly and the safety pin was inserted incorrectly, and on both these occasions the error was made by the same tradesman. On both occasions the error was noticed by customer representatives and brought to the attention of the contractor’s line management. Of note, no ground safety incidents were raised for these errors because an easily accessible, non-punitive and anonymous safety reporting system was not in place, and if there was it was not communicated well.

In the weeks following this incident another procedural issue occurred with contractor’s staff which involved the application of external power to the aircraft without using standard operating procedures. On this occasion, one of the aircraft hydraulic systems was left on when power was applied and there were people standing in area where the doors close. If this error had occurred with an incorrectly inserted safety pin and incorrectly positioned door switch (a part of external power on check), an accident would have been inevitable. This tradesman’s failure to follow procedures was investigated as a result of this incident and she was given remedial training.

Potential Safety Implications

The safety implications of this error have the potential to be fatal. In short, if a person was caught in these doors as they were being closed they would be literally cut in half.

Incident Cause

• Lack of adherence to standard operating procedures.
• Poor or lack of thorough training for the contractor maintenance team on aircraft type.
• The competence of the tradesman could be questioned.
• After discussing the incident with the tradesman he was hesitant about notifying his management of uncertainty or lack of confidence in carrying out the task correctly.
• Poor design on the aging aircraft which could allow the pin to be fitted incorrectly.

Human Factors Lessons

This incident highlights latent errors documented in the Accident Causation Model. Important lessons can be derived from this incident:
• Standard operating procedures need to be trained, followed and their use embedded in the organisations safety culture.
• Training to generate expertise is an important aspect to be managed in a safety management system.
• Building a safety culture with open communication is important in aviation organisations. A ‘rule with an iron fist’ type attitude has no place in aviation at all organisational levels. This would help to mitigate tradesman having fears of ‘putting their hand up’ when they are uncertain, uncomfortable or feel safety and efficiency is being compromised.
• The value in having an easily accessible, non-punitive and anonymous safety reporting system has a necessary place in aviation organisations to allow collection of data on near-misses, incidents and accidents. This will provide data for reducing error and mitigating error consequences.
• Redesign of the safety pin (locking mechanism) is a valid option.

Aviation Project Team Fatigue

Interestingly I work for the same organisation as others who have posted information on maintenance fatigue in this forum, and I would like to comment on an experience I endured while working on a project team.

The organisation I am employed with and its management are well known to employ insufficient manpower on project teams to save costs and this particular project was no different. The project involved the upgrading of the avionics systems on an aging, turboprop aircraft by an overseas based contractor. The project team to be discussed was the customer in this upgrade and our responsibilities involved:
• Maintaining quality assurance,
• Ensuring the project met the contract specification,
• Providing operational and engineering liaison with the contractor,
• Ensuring the basic aircraft systems (non upgraded systems) were serviceable,
• And to ensure my organisation’s standards and documentation were correct and complete.
My role was the lead flight line/hanger specialist on aircraft type in a small engineering and maintenance team with four members (2x engineers and 2x senior technicians).

Over three and half years the aircraft was subjected to a major upgrade to its systems followed by integration and test phase. While the aircraft was in the hangar it was regularly inspected and serviced while in preservation. Prior to the flying phase the aircraft was subjected to a comprehensive wake-up servicing plus functional testing.

As the customer, our under-manned engineering team was responsible to ensure we were ready to fly and all the documentation was complete by a certain date, and this dead line had been set under the contract. The final few weeks leading up to the first flight (Functional Check Flight) were hectic due to the significant amount aircraft documentation, recording and aircraft inspections required. In short, to achieve this task our team worked on average 14-18 hours per day and weekend work for over a week to achieve the deadline. The task was complicated by poor and slow documentation of the work completed by the contractor. In the end our small team met the deadline and the aircraft completed its post-upgrade flight with reasonable success, apart from a flight safety incident which was unrelated to any of the engineering teams actions.

This experience has left lasting impression for me personally of what not to do in aviation and as an aviation human factors manager. Our small team was physically and mentally fatigued after 4-5 days but we pushed on to achieve the task, with a ‘can do attitude’. Key fatigue issues experienced included:
• Making mistakes with the documentation (which were corrected),
• Lost concentration during inspections where I had to walk away at times to clear my thoughts,
• Behavioural issues (Short temper),
• General tiredness and malaise with degrading health and appearance,
• Observation similar issues with my fellow team members.

At one point in the process one of the engineering leads and I put our hands up to demand a break, which did occur but was still not sufficient to relieve our fatigue. We also requested more staff during this period but continually had replies suggesting there was no money to make this happen and no staff available to supplement the team. Operational staff observed and expressed their concern to management of the hours worked by engineering, but the reality was that meeting the deadline was more important, especially for the contractor. Eventually, during the flight testing program, our concerns were recognised and the team’s composition was increased. However, it could be argued the manpower increase was valid and still required at the later date but should been actioned prior to the start of flight testing.

From this experience I learnt the following lessons:
• Fatigue in aviation maintenance is a real threat. Fatigue has the potential to generate latent errors which may go unnoticed until errors line up to create an accident (See Accident Causation Model)
• As a human factors manager in aviation projects or any aviation maintenance operation it is important to ensure there is enough employees or time to allow careful management of employee health and fatigue. This approach will maintain safety and keep the operation more efficient.
• As a human factors manager in aviation maintenance there is a requirement to be aware and understand the risks of pushing team members to their extremes and in this circumstance there was no true requirement. Note, it must be understood in some organisations like the military, there may be a necessary requirement to work to extremes (although it is discouraged).
• As a member at all levels in aviation organisations, and in the interest of maintaining safety and efficiency, there should not be any hesitation in notifying management of unsafe circumstances and practices.
• There is no place for the ‘can do’ approach in aviation if it has negative consequences on safety and efficiency.
• I would like to endorse the lessons learnt on fatigue described by Charger007 and Robere in this forum.
SAFETY is a key requirement or outcome in any aviation maintenance or project activity so contract deadlines and financial drivers must NOT take precedence.

Another recent event which continues to add to my (hopefully) growing knowledge and experience base was the occurrence of a GPWS warning of “Caution Terrain” followed by a further warning of “Terrain Terrain, Pull Up” whilst on the final portion of a Non Precision Instrument approach when still under Instrument Meteorological Conditions. I was the flying pilot and as far as both I and the Captain could establish, was on the correct profile for our distance with speed and decent rate in accordance with company SOPs and the aircraft in the correct configuration (the tower controller was able to also confirm our bearing from the airfield was consistent with what one would expect of an aircraft conducting such an approach but as he had no radar, he could not verify our height).

When carrying out competencies checks, you expect emergencies and abnormal events to occur and so are ready for various things to happen. During a normal shift when such an occurrence presents itself, you definitely notice the greater time it takes to register, process and act on the event. Many studies have examined and shown this over the years, with reaction times of upwards of six seconds noted in pilots responding to a situation (George, 1996). I can recall there being a very real “what is that” moment before processing it, thinking that we were exactly where we should be so why is it going off before calling for a Go around/missed approach and climbing the aircraft away. We tracked towards a hold at safe altitude, checked several aircraft systems, confirmed we had the correct QNH set before trying the approach again for a safe and uneventful landing.

De-briefing the event afterwards I found it interesting that both the Captain and I internally (VERY briefly!) thought about ignoring what was probably a spurious warning before assessing the situation (bearing in mind, such thoughts are happening in a mere matter of seconds), complying with safe practices/SOPs and returning the aircraft to a safe height. It would seem the terrain awareness that my company conducts worked. With everything going on we still both thought briefly about a video all our pilots are shown concerning a 747 operating into Malaysia where the crew descended below the minimum safe altitude, ignored a GPWS warning because of faults the system may have had, only to fly into the side of a hill with the loss of fours lives (see N807FT Crash). False alerts may happen for various reasons and as tempting as it may be to ignore them sometimes, it still pays to listen to them and act accordingly; one of them might just save you one day.

George, F. (1996, March). Rejected Takeoffs. Business & Commercial Aviation, 76-81

During one of my duel CPL nav training exercise, I was flying with my instructor over the eastern part of the north island heading back to palmy. I remeber it was a day with clear blue sky but medium to strong westerly winds. All of a sudden, we encountered heavy turbulance and both of us was not straped tighly enoguh on the seat and was thrown around in the cockpit, bumping our heads into the ceiling. I immeditily applied full power and climbed as I suspected that the turbulance was casued by the ranges below which we started to fly accross, altho we had to bust the airspace, but to me it was an unforgettable experience.

This incident happened on my 2nd solo. I was doing solo circuit practice at NZPM (Palmerston North) with very limited flying experience, approximately about 15 hours. My intention was doing 3 circuits at Palmerston North in order to practice my flying skills. The first circuit was normal. Everything was usual. During the 2nd circuit I was told that: “Due to the arrival of an Air NZ flight, after touch and go continue climbing maintain runway heading until further advised.” Therefore after the “touch and go”, I was climbing on runway heading and waiting for calls from ATC (I thought I was doing as exactly as what tower asked me to do). However, I did not know that I should level off at 1100ft (circuit altitude and NZPM). The traffic around Palmerston was a bit busy, and I did not receive any radio calls from tower for a few minutes. Eventually when tower called me again I got asked to descend immediately and I noticed my altitude was almost at 2000ft (went into Ohakea controlled airspace without clearance). After that I descend to 1100ft and continued a normal circuit with a full stop landing.

What I learned from this incident is that a clear and good understanding of airspace is very important, and it can help understand the instructions obtained from ATC. Secondly, any time if unsure about any clearance, do not hesitate to ask. A confirmation on clearance is better than doing something wrong.

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