B737-800 flight crew experiences a cabin altitude warning horn passing 10;000 FT during climb. Before the aircraft can be leveled the passenger oxygen masks deploy. Rushed approaches result in two go arounds before an emergency is declared and a successful landing ensues. Engine bleeds were 'discovered' in the 'off' position.
Synopsis
B737-800 flight crew experiences a cabin altitude warning horn passing 10;000 FT during climb. Before the aircraft can be leveled the passenger oxygen masks deploy. Rushed approaches result in two go arounds before an emergency is declared and a successful landing ensues. Engine bleeds were 'discovered' in the 'off' position.
Narrative
Climbing out; we received a cabin altitude warning and began a descent below 10;000 FT and requested a return. As a rapid climbout was happening; the cabin altitude raised high enough to deploy the masks in the cabin before we could get back down below 10;000 FT. We were vectored back but were not slowed down and configured to land. Executed a go-around and were given vectors by the controllers back onto final. The weather was marginal VFR and maybe the controllers thought we could see the airport. There was confusion with ATC about how they wanted us back around. Discovered the bleeds were actually in the off position. Bleeds back on and feeling rushed around the pattern in a VFR/IFR situation while working checklist responses put me out of sync and forced another go-around. Third time around; emergency declared; Captain made the approach and landing. Requested EMS meet us at the gate as a precaution. Contributing Factors:1. Switches in this a/c opposite of my last airplane.2. Aircraft coming from the hangar.3. Checklist response (on a/c panel) 'set' Might be better if 'on'4. Controller and weather issues complicating a text-book return for landing.
Second reporter narrative
[We were] climbing out with clearance to climb to 17;000. Passing 10;000; we got the cabin altitude Warning horn. We began the QRH procedure with a descent to 10;000; then 8;000. Aircraft climbed to nearly 14;000 in the transition and the passenger O2 masks deployed. After a delay in communications with the cabin; I verified that the masks had dropped and gave the number 1 Flight Attendant; the TEST for return.We were rushed in our vectored approach and executed a go around. On the subsequent downwind we 'discovered' the engine bleed switches were off. When we tried to reinstate them; condensation formed and created additional confusion in the cabin which required several more calls and PA's from me. Again; behind; I elected to go around. I declared an emergency at this time for handling and concerns over any possible passenger O2 issues with the extra delay in the air. Medical personnel were requested to meet the plane. Rest uneventful.Lessons: 1. 'Set' on the checklist can be too easy to say and then miss.2. Declare an emergency not only for aircraft issues; but also for priority handling.3. In our scenario; passing thru 10;000 in a good climb; this checklist does not really require an 'emergency descent' as the flight attendants were expecting. We calmly went to 10;000.4. Communication to and from the cabin was not easy with horn and masks.5. Re-establishing bleeds caused confusion in cabin and delays with us. No guidance on this.6. Poor sleep in hotel; with alarm going off 3 times may have contributed.7. Try to keep personal issues aside - tough.8. A/C possibly came from hangar overnight with the bleed switches off - not normal position; check hard in this scenario.9. Good check of cabin alt approaching 10;000 a must.
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Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.