Sad accident - poor Press Reporting
I wish to open by expressing my sincere condolences to the family, and friends of those who perished in this tragic and sad accident.
The first thing I want to say is directed at the "Press" for their predicable puerile attacks on the pilots, trying to pin the cause of the accident on DRUGS. Shamefull headline grabbing garbage as usual gentlemen.
Whilst I have always been an ardent admirer of AAIB Accident Reports, I am dismayed at the numerous factual errors and anomalies littering this particular report.
The various off duty times.
Commander:
Previous rest period: Off duty: 2109 hrs on 3 January 2002
On duty: 1100 hrs on 4 January 2002
SIC (Handling Pilot):
Previous rest period: Off duty: 2109 hrs on 3 January 2002
On duty: 1030 hrs on 4 January 2002
1.17.2.1 General
They went off duty at 2130 hrs on 3 January and were due back for duty at 1000 hrs on 4 January, a rest period of 121/2 hours.
---------------------------
The anomaly about the alcohol content of the flight-deck crew:
1.13.2 Toxicology
Toxicological examination revealed detectable amounts of diphenhydramine in both the commander and the handling pilot. No alcohol or drugs of abuse were found in the specimens from either pilot.
Both men had consumed a moderate amount of alcohol on the evening before the accident.....
Yet Appendix 3 states,
"In their hotel, both pilots had a meal that included some alcohol. It is estimated that each man consumed some five units of alcohol before retiring to bed at approximately 2330 hrs.
Records indicated that they checked in at approximately 21.15 hrs and had a meal and some alcohol between 2144 hrs and 2315 hrs, before retiring to bed.
------------------------
How can it be no alcohol was found, yet 0.04mcgs per millilitre of diphenhydramine was detected in the handling pilot, and 0.12mcgs per millilitre in the Commander?
The half-life of five units cannot be that short as to be missed and undetectable in that time frame stated.
Flying hours errors:
Appendix 4:
5 Experience: The captain had roughly 8000 hours experience
Para 1.5: Commander Flying experience:
Total all types: Approximately 10,000 hours
---------------------------------------------
Appendix 3 - Medical Report Addendum
DIPHENHYDRAMINE
2. Toxicological examination revealed 0.12mcgs per millilitre of diphenhydramine in the commander. Diphenhydramine was also detected in samples from the handling pilot, at a level of 0.04mcgs per millilitre.
3. The level of diphenhydramine in the commander was a therapeutic level and suggests that the drug had been taken within a few hours of his demise. The half-life of the drug is between 5-8 hours and comparable levels to those found in the commander were seen experimentally two hours after a therapeutic dose of diphenhydramine.
Technical difficulties made interpretation of the level in the handling pilot more difficult but the evidence indicated that it was highly probable that it corresponded to a therapeutic concentration of diphenhydramine.
[with such a tiny amount detected and the stated technical difficulties, it must be highly debateable why the medical examiner decided to use the words, "highly probable" in such limiting circumstances, given he even mentions that interepretation can be "very difficult"].......
I believe that this indicates both pilots took the drug sometime between 12 to 24 hours before their deaths. However it must be stressed that the problem of post mortem redistribution of drugs makes the interpretation of the levels very difficult (Pounder and Jones 1990).
------------------------------------
I know I'm not medically qualified but I would say the limited amount of this drug in their bodies would not have been sufficiently debilitating to prevent proper and corrective control inputs - as proven by the FDR and the valiant attempts by the Handling Pilot in trying to prevent the aircraft crashing...........
The handling pilot's response was immediate and indicated that he was trying to correct an uncommanded movement of the aircraft............... Therefore, from witness comments, the pilots did not appear to be incapacitated in any way.
----------------------------------
Other guys here have hit the nail on the head - Ice/frost on a supercritical wing do not add up, and there lies the root cause of this accident.
1.18.4.2 Supercritical Wing
The Challenger wing has supercritical aerofoil sections
----------------
Appendix 3:
5. Why both these men should be taking diphenhydramine is open to speculation. [did anybody ask their wife's? Was not the postulated explanations given not enough to overcome speculation?]
1.13.3 Diphenhydramine
Diphenhydramine is a sedative anti-histamine used in a number of cold and allergy preparations on sale to the public. It is also used in a number of products used to aid sleep. Examination of the luggage removed from the wreckage site revealed a number of medications within the baggage belonging to the crew. [is that so rare?]
It is possible that the handling pilot had a cold or similar upper respiratory tract infection and was taking diphenhydramine [did the hotel staff notice or the dispatchers/hear them coughing and sneezing?].
Had the commander developed a similar cold, the handling pilot may have shared his medication with him. It is equally possible that both men had taken this drug to aid sleep and prevent jet-lag. There is no way of knowing [positively] why they took this medication.
In my opinion the most likely explanation is that they took the drug to aid sleep [so why was there other medicinal items in their luggage?]. However, it is certain that both men had taken the drug.
------------------
From the web:
Diphenhydramine, an antihistamine, relieves red, irritated, itchy, watery eyes; sneezing; and runny nose caused by hay fever, allergies, and the common cold. It also may relieve the itching of insect bites, sunburns, bee stings, poison ivy, poison oak, and minor skin irritation. Diphenhydramine also is used to prevent and treat motion sickness, induce sleep, treat Parkinson's disease, and relieve cough caused by minor throat or airway irritation.
-----------------
A huge amount of effort and space in the report gravitated to the "drugs" aspect and not nearly enough on the CLEAN WING.
There's the lesson.
RIP
TG