Human factors played a dooming role in this accident and Boeing's 73 design and procedures somewhat contributed to that (at least in so far as to allowing the holes in the swiss cheese to align).
Centaurus makes some valid points. In fact the report lists Boeing as a latent cause to the accident (quoting from page 159: "Ineffectiveness and inadequacy of measures taken by the manufacturer in response to previous pressurization incidents in the particular type of aircraft, both with regard to modifications to aircraft systems as well as to guidance to the crews")
For the benefit of those who have not read the accident report, here is an extract from the Conclusions/Findings page (page 155) addressing the manufacturer.
3.1.4 Manufacturer
1. The description in the Boeing AMM for the procedure for the pressurization check (under the heading “Put the Airplane Back to its Initial Condition”) was vague. It did not specify an action item that the pressurization mode selector be returned to the AUTO position after the pressurization check.
2. The manufacturer’s Preflight procedure and checklists (Before Start and After Takeoff) for checking and verifying the position of controls on the pressurization panel were not consistent with good Human Factors principles and were insufficient to guard against omissions by flight crews.
3. The manufacturer’s procedures should have contained enough redundancy to ensure that the pressurization system was properly configured for flight. Because the position of the pressurization mode selector was critical for pressurization, the specific action should have been explicitly listed in the checklists referring to the pressurization system (Before Start and After Takeoff).
4. The use of the same aural warning to signify two different situations (Takeoff Configuration and Cabin Altitude) was not consistent with good Human Factors principles.
5. Over the past several years, numerous incidents had been reported involving confusion between the Takeoff Configuration Warning and Cabin Altitude Warning on the Boeing 737 and NASA’s ASRS office had alerted the manufacturer and the aviation industry..
6. Numerous incidents had been reported world-wide involving cabin
pressurization problems on the Boeing 737. A number of remedial actions
had been taken by the manufacturer since 2000, but the measures taken had been inadequate and ineffective in preventing further similar incidents and accidents.
There were 5 recommendations made by the Greek investigators (AAIASB) to the NTSB that concerned Boeing:
4 RECOMMENDATIONS
4.1 Safety Actions Taken or in Progress
4.1.1 To NTSB
4.1.1.1 2005 – 37 On 25 August 2005, the AAIASB recommended to the NTSB that the Boeing Company consider taking action to emphasize flight crew training and awareness in relation to (a) the importance of verifying the bleed and pack system configuration after takeoff and (b) the understanding and recognition of the differences between cabin altitude and takeoff configuration warnings.
Response/Action: On 25 August 2005, the NTSB responded that the Boeing Company was prepared to issue an October 2005 revision to 737-
300/400/500/600/700/800/900/BBJ Flight Crew Training Manuals (FCTM) to include a new section entitled Air Systems/Cabin Altitude Warning reminding flight crews on how to understand and recognize the differences between the two meanings of the warning horn and reminding them of the importance of verifying the bleed and pack system configuration after takeoff.
4.1.1.2 2005 – 38 On 25 August 2005, the AAIASB recommended to the NTSB that the Boeing Company clarify the Aircraft Maintenance Manual (AMM) maintenance procedure for Cabin Pressure Leakage Test (05-51-91) to explicitly specify the actions necessary to complete the maintenance test. Currently, under the title of section F “Put the airplane back to its initial condition”, there were three action items but none of them referred for the pressure mode selector to be placed in the position AUTO.
Response/Action: On 12 October 2005, the NTSB responded that the Boeing Company had released a Temporary Revision to 737-300/400/500 AMM 05-51-91/20 on 29 September 2005 to include a specific step to put the pressure mode selector in AUTO at the conclusion of the cabin pressure leakage test. This change was planned for official release in the 12 January 2006 revision cycle of that manual. The same change to the corresponding 737-600/700/800/900/BBJ and 737-100/200 AMM were planned for official releases in the 21 October 2005 and 1 August 2006 revisions, respectively.
4.1.1.3 2005 – 39 On 13 September 2005, the AAIASB recommended to the NTSB that the Boeing Company consider revising the Aircraft Maintenance Manual (AMM) 05-51-91 by adding an additional step associated with section F (“Put the airplane back to its initial condition”): to re-install the oxygen mask regulators (if removed) per AMM 35-12-00.
Response/Action: On 1 September, 2006, the FAA responded to the Safety Recommendation. The FAA informed the Board that the Boeing 737
Maintenance Review Board Chairman had advised Boeing of the AMM
missing steps in December 2005. Boeing revised the 737-300/400/500 AMM with the 12 January 2006 revision, and added to AMM 05-51-91, paragraph 161 2.F, a step 4 which stated “Move the pressurization mode selector on the forward overhead panel to AUTO”, and a step 5 which stated “If the crew oxygen mask regulator was removed, then install and test the mask demand regulator (AMM 35-12-86/401).” As a result, the FAA (Office of Accident Investigation, Safety Recommendation Review Board) classified the corresponding FAA recommendation as “Closed – Acceptable Action”.
4.1.1.4 2005 – 41 On 23 December 2005, the AAIASB recommended to the NTSB that the Boeing Company consider enhancing the design of the
Preflight checklist to better distinguish between items referring to the air
conditioning and the pressurization systems of the aircraft and to include an explicit line item instructing flight crews to set the pressurization mode
selector to AUTO.
Response/Action: On 10 January 2005, the NTSB responded that the Boeing Company was preparing to issue enhancements to the flight crew procedures associated with the Boeing 737 Cabin Altitude Warning System by issuing a revision to 737-200/300/400/500/600/700/800/900/ BBJ Flight Crew Operations Manuals (FCOM)/Quick Reference Handbooks (QRH). The changes included modification of an existing Normal Checklist (NC), deletion of an existing Non-Normal Checklist (NNC), addition of a new NNC, and change in terminology.
4.1.1.5 2005 – 42 On 23 December 2005, the AAIASB recommended to the NTSB that the Boeing Company reconsider the design of the Cabin Pressure Control System controls and indicators so as to better attract and retain the flight crew’s attention when the pressurization mode selector position is in the MAN (manual) position.
Response/Action: On 30 June 2006, in its comments on the draft Final
Report, the Boeing Company responded that a change in the colour of the
indicator, as specifically suggested by the AAIASB, could provide a
misleading indication to the flight crew that another failure had occurred
requiring additional action
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TR