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Dash 8 - Landing Gear down for ~ 10 mins after take-off
About 15 years ago I flew Lufthansa (Augsburg Airways partner) from London City LCY to Frankfurt am Main on a Dash 8. I was seated by the window and noticed the flight crew didn’t retract the landing gear until about 10 minutes into the flight. The cabin crew even started service with the gear extended. Anyone have an idea why this happened? Thanks
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Brake cooling possibly?
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- Starlionblue
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Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
I can only speculate. Generically speaking, keeping the gear out could be for a few reasons.
- An inoperative wheel brake. You want to stop the wheel spinning before you retract the gear. That being said the Dash-8 retracts fore-aft instead of sideways so there are no massive gyroscopic forces on the gear like with most jets.
- Hot brakes. Keep the gear extended for cooling.
I can't see either of those scenarios requiring ten minutes, though perhaps hot brakes could take that long.
- Overweight for landing. Keep the gear extended to increase fuel burn. This should not be an issue in a turboprop I think.
- Gear/hydraulic malfunction that requires some time to troubleshoot. Since it isn't a "Jesus Christ Emergency" you might as well continue to destination as long as you have enough fuel to get there (or an alternate) with the extra burn. Presumably, FRA is a maintenance base (definitely won't be LCY) so that's where you'd want to be with the issue anyway.
- An inoperative wheel brake. You want to stop the wheel spinning before you retract the gear. That being said the Dash-8 retracts fore-aft instead of sideways so there are no massive gyroscopic forces on the gear like with most jets.
- Hot brakes. Keep the gear extended for cooling.
I can't see either of those scenarios requiring ten minutes, though perhaps hot brakes could take that long.
- Overweight for landing. Keep the gear extended to increase fuel burn. This should not be an issue in a turboprop I think.
- Gear/hydraulic malfunction that requires some time to troubleshoot. Since it isn't a "Jesus Christ Emergency" you might as well continue to destination as long as you have enough fuel to get there (or an alternate) with the extra burn. Presumably, FRA is a maintenance base (definitely won't be LCY) so that's where you'd want to be with the issue anyway.
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Never flown a Dash 8 but there's at least one MEL on the CRJ that requires the gear to hang out for 15 minutes after takeoff. Makes one heck of a noise but other than extra fuel burn is no issue. Off the top of my head I wanna say it's for a deferred main landing gear bay overheat sensor.
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Q400 or earlier Dash?
I’m aware of no checklist item on the early Dashes that require delaying gear retraction but don’t have the books in front of me to look.
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I’m aware of no checklist item on the early Dashes that require delaying gear retraction but don’t have the books in front of me to look.
Sent from my iPhone using Tapatalk
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Really speculating here, but 15 years ago would put the time frame right around the time the Q400s were having gear collapse issues. Any possibility that this may have had something to do with it? Keeping the gear extended for a specific period of time to ensure the system is OK to retract, lower and lock?
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- Starlionblue
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Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
ACDC8 wrote:Really speculating here, but 15 years ago would put the time frame right around the time the Q400s were having gear collapse issues. Any possibility that this may have had something to do with it? Keeping the gear extended for a specific period of time to ensure the system is OK to retract, lower and lock?
You wouldn't gain any additional information about the ability of the gear to downlock again on the next cycle by keeping it downlocked.
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Starlionblue wrote:You wouldn't gain any additional information about the ability of the gear to downlock again on the next cycle by keeping it downlocked.
I didn't think there would be, never flown the Q or any other Dash 8 - but was just wondering if maybe there was an extra item on the checklist after the incidents as there are in other cases.
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- LimaFoxTango
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Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
DashTrash wrote:Q400 or earlier Dash?
I’m aware of no checklist item on the early Dashes that require delaying gear retraction but don’t have the books in front of me to look.
Sent from my iPhone using Tapatalk
Correct. Leaving the gear down for brake cooling or any other reason isn't a thing on a Dash 8 100/300.
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
There is a simpler answer, one that happened to me (8,000 hrs dh8 flying): They forgot to make the "Positive Rate" call, perhaps due to a distraction. KISS.
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Yikes! wrote:There is a simpler answer, one that happened to me (8,000 hrs dh8 flying): They forgot to make the "Positive Rate" call, perhaps due to a distraction. KISS.
Exactly my thoughts. Maybe they were too busy enjoying the London scenery
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Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
Speculation but, the CRJ (both Bombardier products at a point) does have a MEL item for bay overheat inop that requires gear extended for exactly 10 minutes following off. Anyone have a Dash 8 MEL book that wants to see what it has for Bay Overheat detection inop?
Re: Dash 8 - Landing Gear down for ~ 10 mins after take-off
The Dash 8 has no gear bay overheat detection system. There are fire detection loops within the nacelles but they are not for gear bay overheat. Also, the Dash does not have temperature sensors in the brake units, just in case anyone was wondering.
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