Flight Crew Air Transport Pilot (ATP)
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Weather
While in line (#18) for takeoff with the Before Takeoff Checklist completed down to final items; we started to hear reports of wind shear on the tower frequency. There may have also been a wind shear advisory on the ATIS. The Captain decided to change the takeoff thrust setting and use TOGA. I asked if he would also like to use Flaps 2. He said yes and I requested Flaps 2 takeoff data from the ACARS. While I was doing this the Captain began reprogramming the Perf page by entering 2 in the Flap setting. When we received the Takeoff data; we had a long discussion about what speeds he wanted for takeoff. He decided to use the Max thrust V-speeds for V1 and Vr and a speed of 142 for rotate. This speed was well below the 154 Vr maximum listed on the data; but he chose it because it matched the 10 knot tailwind Vr for a reduced takeoff (I guess this is his technique). I programmed the speeds into the Perf page and shortly thereafter we departed 4L; rotating at 142 knots. At 800 feet AFE; upon power reduction; the Captain noticed and stated that the flaps were still at position 1 and that we had never set Flaps 2. We discussed what had occurred and compared the speeds we had used with the Flaps 1 data. It appeared that we rotated 4 knots below the rotate speed for Flaps 1 reduced; but I didn't think to compare it to the Vr speed on the TOGA thrust line for the Flaps 1 data.The error was that we did not comply with the flight manual and repeat the Before Takeoff Checklist after repositioning a flight control. Other contributing factors were my flow for setting the new Flap position on the Perf page followed by moving the flap lever to the proper position was interrupted by the Captain selecting position 2 on the Perf page; the extensive discussion on V-speeds; and the first time flying together with this out of domicile Captain.
This was first flight as a crewWondering why the backup [for takeoff]; we were told there were reported 15 knot wind shears on approach and takeoff. I stated we should swap to TOGA power and the First Officer (FO) asked should we consider flaps 2. I agreed. While he got the performance data I set 2 in the performance page of the FMC. We briefed the flaps two data and also that we would delay rotation slightly using V1 VR and 'rotate' at a higher speed using the flaps 2 data. After the briefing we should have run the takeoff checklist again; but we both forgot. This led us to not resetting the flap lever to 2 even though all plans now were for flaps 2 and TOGA.
An A320 flight crew; number 18 for takeoff due to reported windshear; reports on takeoff and landing; wisely opted to change their takeoff configuration to flaps position two and TOGA power as a precaution. They programmed new performance numbers based on the new configuration but failed to repeat the before takeoff checklist after doing so. During climbout they realized they had not reset the flaps and they had remained in their original flaps one position.