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A part task trainer (PTT) is a training device that is designed to train a member of the aircrew or maintenance staff on a particular task associated with the aircraft. Various providers have designed and developed part task trainers for a range of tasks including:

  • Avionics systems.
  • Systems familiarization.
  • Health monitoring systems, and
  • A variety of complex tasks specific to a particular aircraft.
  • Part-task simulators can be used for crew training for preflight checks, normal and abnormal/failure operations primarily when using the autopilot. Software MUST be totally accurate.

Potential hazard

  1. Part-task trainers and limited range of motion high-fidelity simulators may not sufficiently emulate loss-of-control situations to enable effective upset recovery training.
  2. Negative transfer of training due to the lack of fidelity with the actual operational environment. For certain accident types, training may not help; aircraft changes may well be necessary.
  3. Poorly modeled aircraft dynamics and control laws. Upset prevention (via recognition) may improve using part-task simulators, but actual ability to recover from unusual attitudes may worsen.
  4. Airline crews learning tricks to fly the simulator and pass competency checks
  5. Unrealistic handling in strong or gusty crosswinds
  6. However, some simulators may be particularly effective in training for recognition and early detection of the conditions preceding loss of control situations. Implementation may be more widespread due to lower cost of part-task trainers.
  7. There is a risk of pilot training in aircraft handling, including loss of engine power and asymmetric flight being carried out on the aircraft rather in flight than in full flight simulator. Control of an aircraft near V1 on the ground or at low altitude after take off cannot be adequately simulated at higher altitudes.

Corroborating sources and comments Jan, 2011 – Mahadevan, Nagabhushan, Abhishek, Dubey and Karsai, Gabor, A Case Study On The Application of Software Health Management Techniques, TECHNICAL REPORT, SIS-11-101

Due to the increasing software complexity in modern cyber-physical systems there is a likelihood of latent software defects that can escape the existing rigorous testing and verification techniques but manifest only under exceptional circumstances.

These circumstances may include faults in the hardware system, including both the computing and non-computing hardware. Often, systems are not prepared for such faults. Such problems have led to number of failure incidents in the past, including but not limited to those referred to in this study:

Ariane 5 inquiry board report. Technical report, Available at:, June 1996.

A. T. S. Bureau. In-flight upset; 240km nw perth, wa; boeing co 777-200, 9m-mrg. Technical report, August 2005.

T. S. Bureau. Ao-2008-070: In-flight upset, 154 km west of learmonth, wa, 7 october 2008, vh-qpa, airbus a330-303. Technical report, October 2008.

W. S. Greenwell, J. Knight, and J. C. Knight. What should aviation safety incidents teach us? In SAFECOMP 2003, The 22nd International Conference on Computer Safety, Reliability and Security, 2003.

NASA. Report on the loss of the mars polar lander and deep space 2 missions. Technical report, NASA, 2000.

Level D full flight simulators (FFS) are not needed for all areas of pilot training and other PTTs can more than adequately serve their purpose fully when it comes to providing what is needed. Notes on hazards shown:

1. Many argue the merits of an FFS device. Some will argue the lack of adequate or sufficient ‘realism’ for training some more specialized events, such as URT or LOC-I. The reality is that simulation will always have the limitation of gravity or the lack of it to be more precise. We will never train for Upset Recovery Training (URT) in a flight simulator with g-feedback. It’s just not possible. We can however train procedure and imprint recovery.

For proper G-force feedback the pilot will have to use a real aircraft and most airlines will not want to expose their valuable assets to the risks associated with that training. That’s how we ended up with full flight simulators.

2. This will always be the case. Newer technology full flight simulators will be a problem. With respect to flight data packages, the simulation will have its limits. Should a user wish to program events beyond the modeled environment the computer will respond as it always has, GIGO.

3. Again, g-feedback is not a possibility in FFSs. The fact a pilot may overload or exceed stress tolerances during an upset recovery remains a possibility. The broad range of potential LOC-I or Upset scenarios makes it difficult to establish a one-size-fits-all strategy. Why modeled aircraft dynamics and control laws would miss the scrutiny of an approval process for certification is unclear. Most simulator test and evaluation pilots have not experienced this problem.

4. This goes back to years of fostering an attitude among pilots that the PTS standard breeds an attitude among airline pilots who only want to train for their test and only want to pass the test. Many airline pilots say they don’t want to know anything but what’s on the test. With greater fidelity in simulation today, it is less likely a pilot can or is able to ‘learn tricks’ to fly a simulator to pass a checkride.

5. The requirement for simulator certification of crosswinds is 15% of the demonstrated crosswind component for the real aircraft. Like any computer, once again, GIGO. If an instructor inputs a crosswind that goes beyond the 15% factor in the simulator data package it will produce unrealistic handling in strong gusty crosswinds. Pilots need to respect the crosswind limitations of their aircraft as recommended by the OEM. (2009)

Importance of Maintaining V2 in the Climb: D228, vicinity Kathmandu Nepal, 2012 (LOC HF),_vicinity_Kathmandu_Nepal,_2012_(LOC_HF)?utm_source=SKYbrary&utm_campaign=7447a5c9ed-SKYbrary_Highlight_04_07_2013&utm_medium=email&utm_term=0_e405169b04-7447a5c9ed-276463842

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