For the record I have flown both Boeing and Airbus, and can find merits in both series. As others have probably agreed to- in general, the Boeing are easier to handle wrt to systems malfunctions, the Airbus, more comfortable to operate in normal ops, but you have to be thorough during non normal ops.
Over the last 10 years Airbus have become increasingly easier to operate wrt to non normals, and I believe the 380 has an electronic checklist and a very comprehensive EFB.
Irrespective of the merits of both types, and the preferences of the pilots, a company's decision on aircraft orders is solely bases upon the financial benefits in maximising profit for the company. Therefore it is pointless to rant on about how good a 380 is or a 777 is from a pilots perspective. If Tim clark could work a profit out of using Cessna 172s then we would all be flying them. Period.
However, in the spirit of gentlemanly debate I feel it necessary to point out some incorrect assumptions I have viewed here.
Bypass Ratio-
But an Airbus will let you make an error of 100tonnes into the FMC to generate takeoff speeds??
This type of error is not relegated to just airbus. See here for other aircraft types with a similar error.
Summary of occurrences
Boeing 747: May 2002
Location: London, UK
During the take-off run, the aircraft’s rotation was initiated at a low speed. The rate of rotation was reduced to allow the speed to increase for climb out. A reduction to the V1 speed due to a wet runway resulted in an incorrect rotation speed (VR) being entered into the aircraft’s flight management computer (FMC).
Boeing 737: November 2002
Location: Townsville, Qld
When preparing the aircraft for departure, the crew were required to read the final loadsheet figures directly from the aircraft communications addressing and reporting system (ACARS) as the ACARS printer was unserviceable. Both crew members selected the ACARS message page on their respective control display unit (CDU) when the final loadsheet was received and the message was acknowledged on the first officer’s CDU. The load figures were then read aloud from the captain’s CDU and copied onto the take-off data card. When doing this, the flight number was misread and the load figures from the previous flight were used. The zero fuel weight (ZFW) entered into the FMC was about 2.8 tonnes less than the actual ZFW. The error was identified during the preparation of the take-off data card and the FMC was amended accordingly.
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Boeing 737: March 2003
Location: Darwin, NT
The crew calculated the take-off performance parameters for a full length runway departure and entered the corresponding V speeds into the FMC. The takeoff was then amended for an intersection departure. The crew briefed on the new V speeds and set their respective airspeed indicator speed bugs. The FMC was not updated with the new V speeds. The crew noticed the error during the take-off run. This resulted in a higher VR speed being used than that required for the reduced runway length.
Boeing 767: April 2007
Location: Melbourne, Vic.
On arrival at the aerodrome, the crew were advised by engineering personnel that an incorrect performance limit manual was found on board the aircraft. The manual was for a Boeing 767 aircraft with different engines. The crew determined that the take-off performance parameters for the previous two sectors were calculated using this manual. The aircraft model variant name was not written on the specific charts. The crew re-calculated the parameters using the correct performance limit manual and identified that only two V speed values varied, with a maximum difference of 8 kts.
Boeing 737: September 2007
Location: Alice Springs, NT
In preparation for takeoff, the crew calculated the take-off performance data based on a required navigation performance (RNP) departure. While taxiing, the crew were advised by air traffic control (ATC) that there would be a delay for the RNP departure due to an inbound aircraft that required priority. The crew received a revised clearance from ATC to conduct a visual departure. After takeoff, the crew realised that the takeoff data had not been checked or amended to take into account the revised departure clearance.
Airbus A320: November 2007
Location: Cairns, Qld
During the take-off run, the thrust setting applied was not as expected. The captain checked the multifunction control and display unit (MCDU) take-off page and noticed that an incorrect FLEX temperature had been entered. Take-off/go-around (TO/GA) thrust was applied. The takeoff and climb out proceeded normally.
The maximum flex temperature had been entered into the MCDU instead of the actual flex temperature. Both figures were positioned next to each other on the take* off data card.
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Airbus A320: March 2008
Location: Launceston, Tas.
The crew incorrectly transposed the take-off safety speed (V2) onto the take-off data card. During the take-off run, the crew noticed the error and continued the flight. Take-off/go-around thrust was applied and the correct V2 speed was selected. The crew commented that they must prioritise standard operations, despite other distractions.
Boeing 747: September 2008
Location: Sydney, NSW
While preparing the aircraft for departure, the crew noticed that an error had been made when entering the mean aerodynamic chord (MAC) take-off weight (TOW) into the FMC cruise page. In order to amend the MAC TOW, the crew were required to enter a false ZFW into the FMC, which then allowed the correct MAC TOW to be entered. The correct MAC TOW was entered into the cruise page. At the same time, the first officer recalled hearing the captain state that the correct ZFW was entered into the left FMC. The first officer then entered the MAC TOW and the decision speed (V1) into the FMC takeoff reference page.
Prior to pushback, the second officer noticed that the V2 speed on the mode control panel (MCP) (168 kts) differed from the speed in the FMC (158 kts). The second officer investigated the discrepancy and discussed it with the other crew members.
The captain stated that he was using new bifocal glasses and when looking at the FMC he was unable to see the MCP clearly through the upper portion of the glasses. It was assumed that an error was made when entering the speed into the MCP and the speed on the MCP was changed to 158 kts.
During the takeoff, the aircraft appeared to feel ‘lighter’ than normal. The captain later observed a discrepancy with the fuel and time estimates on the FMC. The captain explored the situation and discovered that the ZFW entered in the FMC was incorrect; the ZFW was updated accordingly.
Simulations performed by the airline determined that the aircraft was rotated about 13 kts below the correct speed. The crew were only required to manually calculate V1, as VR and V2 were automatically generated by the FMC. Consequently, any change to the ZFW figure in the FMC resulted in a change to VR and V2.
Airbus A320: October 2008
Location: Rockhampton, Qld
When the crew selected the take-off thrust, no information appeared on the flight mode annunciator (FMA). At about 80 kts, the captain (pilot flying) called ‘no FMA’ and the takeoff was rejected. At the same time, an alert appeared on the electronic centralised aircraft monitoring (ECAM) system. The crew determined that an incorrect FLEX temperature had been entered into the MCDU.
While taxiing the aircraft for departure, the temperature on the automatic terminal information service had changed to 26 degrees, which was higher than the FLEX temperature set (21 degrees). This situation would have resulted in the full authority digital engine control (FADEC) system being set at maximum continuous thrust,
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while the thrust levers were set to FLEX for takeoff. The error was not detected by the crew when completing the checklist as there was only a requirement to compare the MCDU and upper ECAM display, not the take-off data card, where the temperature values were written.
Airbus A320: May 2008
Location: Sydney, NSW
In preparation for departure, the crew inadvertently used the take-off performance data for an Airbus A321 aircraft instead of an Airbus A320 aircraft; the data for both aircraft were similar. It was reported that the aircraft type was written in a small font on the front page of the reference document and title area on the take-off performance page.
Mention has been made here about the non feed back of Airbus side sticks, whilst true that there is no direct tactile feed back, there is a loud audio and visual cue in front of the pilots eyes on the Glare shield. A loud Audio Alert DUAL INPUT Sounds and a PRIORITY LEFT/RIGHT Audio and Visual RED Arrow cues available. Clearly and tragically this was not interpreted by the operating pilots on the Air France case.
Similarly the Tactile moving AutoThrust Cues were not detected by the Turkish air Crash when their throttles moved into a flare mode and stayed there til it was too late to recover.
