N243NW From United States of America, joined Jul 2003, 1494 posts, RR: 21 Reply 2, posted (2 years 3 months 1 day 2 hours ago) and read 3564 times:
I'm not an expert on the heavy iron, so I'll leave it to our resident airline pilots.
However, on the PA28R and PA44 general aviation airplanes (which I have plenty of experience in), the landing gear unsafe light illuminates and the horn sounds under the following conditions:
- The flaps are set past 10 degrees with the landing gear down limit switches not engaged (gear not down)
- The power is reduced past approximately 14" MP with the landing gear down limit switches not engaged (gear not down)
- The landing gear selector is in the "UP" position with the airplane on the ground (squat switch engaged)
Some of the older Arrows (I've flown one) were produced with an automatic gear extension system that automatically drops the gear when the airplane slows below a certain airspeed. Sounds like a swell idea, but many planes had it removed for several reasons. First, no one really knew exactly what this magic airspeed was for any given aircraft, the system that sensed the airspeed (it looks like a second pitot/static mast with a garden hose attached to it in the cabin) was darn near impossible to calibrate, and often the gear would free-fall when you definitely didn't want it extended (like during an engine failure...the plane glided like an anvil and the gear didn't help matters). For this reason, in the event of an engine failure at altitude the first thing I was trained to do was lock the gear up with the override until I was certain I would make the intended landing field. Big pain in the rear if you ask me.
regliner From United States of America, joined Feb 2011, 18 posts, RR: 0 Reply 3, posted (2 years 3 months 22 hours ago) and read 3516 times:
Not a pilot, just a mechanic. A heavy pilot can correct me if I'm wrong.
In large commerical theres logic (airspeed, altitude, flap position, etc) that will set off an aural warning if the logic critia isn't met. So if the plane thinks it's landing and the gear isn't down a voice will say "too low, Gear" and I believe you get a yellow caution message
"Plane's don't fly in the air. They fly on paper!"
YYZatcboy From Canada, joined Apr 2005, 809 posts, RR: 0 Reply 4, posted (2 years 3 months 21 hours ago) and read 3501 times:
Also might set off the GPWS
"TOO LOW, TERRAIN, PULL UP"
Windshear warning will still trump it though, so theoretically you can land with the gear down with no warning if the predictive windshear warning is going off. (but really, would you be landing with that warning anyway?)
jetlagged From United Kingdom, joined Jan 2005, 2452 posts, RR: 17 Reply 6, posted (2 years 3 months 17 hours ago) and read 3434 times:
A landing gear warning horn is very common. They used to be simple devices which sounded when the throttle was closed with the gear retracted. Flap position and radio altitude are commonly added to the logic to reduce nuisance warnings.
For example, on the 747-200, the horn will sound if the throttle is closed with gear up and LE flaps extended, but it can be cancelled with a button on the pedestal. If flaps are greater than 23 degrees (i.e. in landing position) the horn will sound regardless of throttle position and it can't be cancelled. The landing gear not locked down red lights illuminate whenever the horn sounds. The red lights also illuminate if the throttles are closed and the gear is retracted regardless of flap position.
GPWS/EGPWS gear warnings mentioned in posts above are additional to aircraft landing gear aural warning systems. The logic depends on what version of GPWS/EGPWS is installed, not the aircraft type.
The glass isn't half empty, or half full, it's twice as big as it needs to be.
tb727 From United States of America, joined Jun 2005, 1375 posts, RR: 4 Reply 7, posted (2 years 3 months 15 hours ago) and read 3353 times:
It usually turns into a game. "Coming back" is a common phrase to have the other guy or FE grab the horn silence lever when you pull the throttles to idle in flight up high with the gear up. If they miss it they owe you a frosty cold beverage.
kalvado From United States of America, joined Feb 2006, 471 posts, RR: 0 Reply 8, posted (2 years 3 months 14 hours ago) and read 3320 times:
Quoting tb727 (Reply 7): It usually turns into a game. "Coming back" is a common phrase to have the other guy or FE grab the horn silence lever when you pull the throttles to idle in flight up high with the gear up. If they miss it they owe you a frosty cold beverage.
Probably off-topic.. But - if they make it, do they enjoy a drink charged to your bill?
bio15 From Colombia, joined Mar 2001, 1089 posts, RR: 7 Reply 9, posted (2 years 3 months 10 hours ago) and read 3258 times:
On the 737NG (not sure on the Classics) you'll get the following alerts for a retracted landing gear during landing:
1 - Visual landing gear position indicator lights (the usual green/red/off lights)
2 - Landing Gear Horn (It's pretty loud). It will sound if any landing gear is not down and locked, and:
- Flaps are from UP to 10º, and below 800 ft AGL with any thrust lever angle below 20º (34º engine out)
- Flaps are from 15º to 25º, and any thrust lever angle below 20º (34º engine out)
- Flaps are beyond 25º
3 - "TOO LOW GEAR" EGPWS Warning, when flying low at low airspeed with landing gear not down
4 - A very perceptive Tower controller!