767 out of YBCS today.
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Join Date: Sep 2001
Location: Over the Rainbow
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767 out of YBCS today.
Heard a remark today from a 767 crew to the Cairns tower it went along the following lines:
767: ...you might notice our gear will be a little slow to retract today, there is no cause for alarm...
Tower said that was ok.
What would be the reason for this slow gear problem anyone?
767: ...you might notice our gear will be a little slow to retract today, there is no cause for alarm...
Tower said that was ok.
What would be the reason for this slow gear problem anyone?
Join Date: Mar 2002
Location: north of the border
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Wouldnt taxi if brakes too hot, as this would effect RTO performance.
I think more than likely that the Air Demand Pump (ADP), was u/s.
Centre hydrualic system has a bleed air powered ADP, Which in auto mode comes on to assist in powering the centre system with heavy load items, ie; gear, flaps/slats, spoilers etc.
Gear retraction may take up to 3 mins? ( I think, ground school was a while ago), which obviously has an effect on climb performance and therefore RTOW.
Maybe the answer.
I think more than likely that the Air Demand Pump (ADP), was u/s.
Centre hydrualic system has a bleed air powered ADP, Which in auto mode comes on to assist in powering the centre system with heavy load items, ie; gear, flaps/slats, spoilers etc.
Gear retraction may take up to 3 mins? ( I think, ground school was a while ago), which obviously has an effect on climb performance and therefore RTOW.
Maybe the answer.
Join Date: Jun 2001
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The takeoff weights are invalidated if the gear is left down - but that really is irrelevant because if there were 2 engines running the RTOW doesn't, strictly speaking apply either..
By that I mean the RTOW weights are the weights that the aeroplane can lift if it suffers a failure at Vef and continues, these weights being predicated on a number of things, one of which is the gear being up.
If the gear couldn't be retracted immediately if required a new RTOW chart that accounts for the penalty would be required, but that would SERIOUSLY limit the weights - assuming that one could be calculated by ops engineering, or you wouldn't go.
By that I mean the RTOW weights are the weights that the aeroplane can lift if it suffers a failure at Vef and continues, these weights being predicated on a number of things, one of which is the gear being up.
If the gear couldn't be retracted immediately if required a new RTOW chart that accounts for the penalty would be required, but that would SERIOUSLY limit the weights - assuming that one could be calculated by ops engineering, or you wouldn't go.
The MEL permitting dispatch with the Centre Hydraulic system Air Driven Pump (ADP) inoperative details the performance penalties that must be applied. The max RTOW is significantly reduced because of the degraded 2nd segment, however, if the aircraft was operating on a domestic sector then the actual TOW would be much much lower than the new RTOW.
L84Wrk is correct in his post as the two electric pumps on the Centre Hydraulic system would retract the gear normally except that with a lower flow rate it may take up to 3 minutes.
L84Wrk is correct in his post as the two electric pumps on the Centre Hydraulic system would retract the gear normally except that with a lower flow rate it may take up to 3 minutes.
or.....one brake inop....equals no autobraking during gear retraction....equals gear left down for two minutes after takeoff to allow wheel spindown....equals 18,000kg performance penalty!
