Multi-million dollar simulators yet max crosswind practice is avoided.
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Centaurus
It is well-known that it is extremely difficult for pilots to assess the accuracy of flight simulators. It is proven to be too subjective in many occasions. A study I have recently seen (done by a large airline) asked pilots about the accuracy of simulators in representing gusty crosswind. The outcome simply gave a normal distribution with the average at neutral and as many pilots saying it was very bad to very good.
If level D simulators/engineering simulators are good in representing gusty crosswind why are we still doing time consuming and expensive flight tests to demonstrate a certain crosswind?
It is interesting to have a look at the NTSB report on the B737 excursion. I picked a few lines from this report.
NTSB report AAR10-04, Boeing 737-500, NN186111, Denver, Colorado, December 20, 2008
Contributing to the accident were the following factors: ..... and 2) inadequate crosswind training in the airline industry due to deficient simulator wind gust modeling.
“the company’s 737-500 flight simulators (in which the captain likely accomplished this training) were not programmed to simulate gust effects below about 50 feet above the ground and, therefore, were not capable of replicating the complex disturbances that pilots would experience during takeoffs and landings in gusty surface winds.”... “Continental discovered that its FFS atmospheric model software allowed for only steady state wind inputs—no gusting winds—below 50 feet agl. Before this discovery, Continental’s simulator instructors were unaware that the simulator would not apply gusty winds below 50 feet agl, regardless of their manual inputs to the system.”
“Although much work has been done to improve the fidelity of flight simulators in recent decades, the NTSB is unaware of any recent efforts to improve the fidelity of the wind models used in simulators for the training of gusty crosswind takeoffs and landings.”
“After completing takeoffs in all four crosswind conditions, some participants stated that the task did not seem that difficult overall. They also stated that the simulator did not accurately reflect lateral forces, nor did it provide as good of a “seat-of-the-pants” feel for wind gusts as an airplane would.”
NTSB recommendations:
Gather data on surface winds at a sample of major U.S. airports (including Denver International Airport) when high wind conditions and significant gusts are present and use these data to develop realistic, gusty crosswind profiles for use in pilot simulator training programs. (A-10-110)
Require 14 Code of Federal Regulations Part 121, 135, and 91K operators to incorporate the realistic, gusty crosswind profiles developed as a result of Safety Recommendation A-10-110 into their pilot simulator training programs. (A-10-111)
From personal experience at strong crosswind landings real time in a 737 I have found the 737 Level D FFS I have operated have shown excellent fidelity in strong crosswinds.
If level D simulators/engineering simulators are good in representing gusty crosswind why are we still doing time consuming and expensive flight tests to demonstrate a certain crosswind?
It is interesting to have a look at the NTSB report on the B737 excursion. I picked a few lines from this report.
NTSB report AAR10-04, Boeing 737-500, NN186111, Denver, Colorado, December 20, 2008
Contributing to the accident were the following factors: ..... and 2) inadequate crosswind training in the airline industry due to deficient simulator wind gust modeling.
“the company’s 737-500 flight simulators (in which the captain likely accomplished this training) were not programmed to simulate gust effects below about 50 feet above the ground and, therefore, were not capable of replicating the complex disturbances that pilots would experience during takeoffs and landings in gusty surface winds.”... “Continental discovered that its FFS atmospheric model software allowed for only steady state wind inputs—no gusting winds—below 50 feet agl. Before this discovery, Continental’s simulator instructors were unaware that the simulator would not apply gusty winds below 50 feet agl, regardless of their manual inputs to the system.”
“Although much work has been done to improve the fidelity of flight simulators in recent decades, the NTSB is unaware of any recent efforts to improve the fidelity of the wind models used in simulators for the training of gusty crosswind takeoffs and landings.”
“After completing takeoffs in all four crosswind conditions, some participants stated that the task did not seem that difficult overall. They also stated that the simulator did not accurately reflect lateral forces, nor did it provide as good of a “seat-of-the-pants” feel for wind gusts as an airplane would.”
NTSB recommendations:
Gather data on surface winds at a sample of major U.S. airports (including Denver International Airport) when high wind conditions and significant gusts are present and use these data to develop realistic, gusty crosswind profiles for use in pilot simulator training programs. (A-10-110)
Require 14 Code of Federal Regulations Part 121, 135, and 91K operators to incorporate the realistic, gusty crosswind profiles developed as a result of Safety Recommendation A-10-110 into their pilot simulator training programs. (A-10-111)
the NTSB is unaware of any recent efforts to improve the fidelity of the wind models used in simulators for the training of gusty crosswind takeoffs and landings.”
From the excellent points put forward in earlier posts I must say I am now confused whether full flight simulators have the fidelity for steady crosswinds. I accept that gusty crosswinds are a fidelity problem.
If steady crosswinds cannot be handled by the simulator then why do type rating syllabus and recurrent training such as LOFT, allow crosswinds to be set by the simulator instructor?
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Hi Centaurus,
Have you viewed David Learmount's experience in post 12?
Sim motion can't be faithful due to the physical restrictions of the motion legs.
1) Turning on the ground is confusing because you inner ear senses the heading change in real life, but is absent in the sim.
2) Likewise the heading change during align in a big crosswind can not be felt.
3) No sense of long term delta g in the sim during TCAS Events, take off or landing.
So those clues you feel in your stomach telling you how hard you are pulling are missing, and so are the heading changes sensed by the inner ear. In real life you'll use those clues. In the sim - only the picture changes and corresponding flight instruments.
Provided you recognise those motion deficiencies, the sim is a very useful tool for teaching techniques. Experienced pilots find real flying easier to handle than the sim.
Have you viewed David Learmount's experience in post 12?
Sim motion can't be faithful due to the physical restrictions of the motion legs.
1) Turning on the ground is confusing because you inner ear senses the heading change in real life, but is absent in the sim.
2) Likewise the heading change during align in a big crosswind can not be felt.
3) No sense of long term delta g in the sim during TCAS Events, take off or landing.
So those clues you feel in your stomach telling you how hard you are pulling are missing, and so are the heading changes sensed by the inner ear. In real life you'll use those clues. In the sim - only the picture changes and corresponding flight instruments.
Provided you recognise those motion deficiencies, the sim is a very useful tool for teaching techniques. Experienced pilots find real flying easier to handle than the sim.
Last edited by rudderrudderrat; 25th Dec 2011 at 18:37. Reason: can't spell
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In one old 727-200 sim we had at TAA you could roll it on its
back and fly the ILS upside down. Took some finesse and lots
of practice (I was just a sprog FO with only 3000 odd hrs TT
in me log book) but eventually nailed it to renewal standards.
back and fly the ILS upside down. Took some finesse and lots
of practice (I was just a sprog FO with only 3000 odd hrs TT
in me log book) but eventually nailed it to renewal standards.
N4790P
Centaurus,
It was never in doubt. They had the ultimate in simulation – The C-11A Shuttle Training Aircraft. (I had the pleasure of seeing a presentation by the (newly redundant) Shuttle Project Manager a few months ago when he described how a Shuttle Pilot had to successfully accomplish 500 landings in the C-11A and a Shuttle Commander 1000 landings before an actual Shuttle launch. Very, very impressive).
Makes you wonder how the Space Shuttle crew handled their flight when the fidelity of their simulator was in doubt.
