Originally Posted by
AirRabbit
I wonder … have you ever read through the theory and requirements of airplane design and construction? Have you ever reviewed, even casually, the specific standards that are required to be met, and the lengths to which everyone must go – all while under strict supervision and regular checking – in order to have the work they have completed be approved for their specific contribution to the process that takes an airplane from a pen-and-paper design to being a functional airplane in flight? .
No I have not read the endless information about certification and have no intention of doing so. I have read plenty of accident reports though such as the ones I mentioned earlier. While your blind faith in certification is commendable, the line of thinking has had multiple failures over the years including but not limited to the accident I started earlier.
1) Air France Concorde: "
in-service experience shows that the destruction of a tyre during taxi, takeoff or landing is not an improbable event on Concorde and that such an event may cause damage to the structure and systems. However, such destruction had never caused a fuel fire.
The accident which occurred on July 25 2000 showed that the destruction of a tyre - a simple event which may recur - had catastrophic consequences in a very short time without the crew being able to recover from the situation.
Consequently, without prejudice to further evidence that may come to light in the course of the investigation, the BEA and the AAIB recommend to the Direction Générale de I'Aviation Civile of France and the Civil Aviation Authority of the United Kingdom that the Certificates of Airworthiness for Concorde be suspended until appropriate measures have been taken to guarantee a satisfactory level of safety with regard to the risks associated with the destruction of tyres.”
http://www.bea-fr.org/docspa/2000/f-...sc000725a.html
2) United 811 in Hawaii - Contributing to the cause of the accident was a deficiency in the design of the cargo door locking mechanisms, which made them susceptible to deformation, allowing the door to become unlatched after being properly latched and locked. Also contributing to the accident was a lack of timely corrective actions by Boeing and the FAA following a 1987 cargo door opening incident on a Pan Am B-747.
http://www.ntsb.org/Wiringcargodoorl...es/AAR92-3.pdf
3) United DC-10 Sioux City - The Safety Board considers in retrospect that the potential for hydraulic system damage as a result of the effect of random engine debris should have been given more consideration in the original design and certification requirements of the DC-10 and that Douglas should have better protected the critical hydraulic system(s) from such potential effects. As a result of lessons learned from this accident, the hydraulic system enhancement mandated by AD-90-13-07 should serve to preclude loss of flight control as a result of a No. 2 engine failure. Nonetheless, the Safety Board is concerned that other aircraft may have been given similar insufficient consideration in the design for redundancy of the motive power source for flight control systems or for protecting the electronic flight and engine controls of new generation aircraft.
http://www.airdisaster.com/reports/ntsb/AAR90-06.pdf
4) Turkish DC10 - Following the American Airlines event, the FAA had written, but not released, an Airworthiness Directive aimed at correcting the cargo door failure. McDonnell-Douglas developed three service bulletins for modification of the cargo door, and proposed to the FAA that rather than issue an AD, the FAA allow the manufacturer to issue the service bulletin as mandatory (an unprecedented action for an urgent safety issue of this magnitude). The FAA concurred with this proposal, and the service bulletins were issued, but their incorporation was not mandated by the FAA. Many carriers voluntarily incorporated the service bulletin modifications, and retrained ground personnel on the proper operation of the door closure mechanism. At the time of the accident, Turk-Hava had only incorporated two of the three service bulletins, although airplane maintenance records reflected that all three had been incorporated. The lack of the final modification, and the fact that the modifications had not been mandated by the FAA was viewed as a major factor in the chain of events leading to this accident.
http://lessonslearned.faa.gov/ll_main.cfm?TabID=1
Originally Posted by
AirRabbit
With specific reference to one of your statements … “a critical engine failure scenario with min V1 being slightly higher than VMCG … is not nearly as safe as you state to just continue” … let me offer the following:
If the engine were to fail – calling into play the VMCG issue – and if the failure were to occur prior to V1, the established standards would call for the pilot flying to reject the takeoff. Of course the airplane would be below VMCG but that should not be an issue in controlling the airplane as the controls used would be the nosewheel steering and wheel brakes.
However, on the other hand, if the engine failure were to occur after V1, again, the established standards would call for the pilot to continue the takeoff. Of course until reaching VMCG the pilot would have to maintain directional control through the use of the same nosewheel steering (either rudder pedal or “tiller” depending on the degree of asymmetrical thrust encountered with the failed engine) which is what the pilot would have been using up to that point.
Really, with a 30 knot crosswind from the adverse side. Based on all those certification test done on calm wind mornings and evenings. As well, I would suggest staying off the tiller. Most aircraft recommend using it for lower speeds only.