Rumor Mill
#33
Line Holder
Joined APC: May 2015
Posts: 92
In the 175 if you encounter icing in the climb or cruise you have to use icing speeds even if you've clearly shed all the ice. It posts an EICAS message that doesn't go away and increases shaker activation point until landing.
So if you pick a tiny bit of ice on the climb, you still have to land with ice speeds even if it's been 2 hours and there's clearly no ice.
Edit: was looking at wrong numbers, should be no problem.
Second edit: was looking at correct numbers:
Lowest distance requirement flaps full with ice speeds and 5/5/5/ is 4830. EYW runway is 4801. That's at 50,000lbs. With anything resembling a normal load you're not landing.
With a dry runway things are tight, but not as bad. ISA, calm wind, flaps full, and ice accumulation you are good up to 67,500lbs (with interpolation). So light pax load, dry runway, and no alternate fuel you'll probably be ok but anything else is going to be a diversion.
I haven't looked at takeoff numbers but my guess is they're pretty tight as well. Although flaps 4 may alleviate a lot of that.
So if you pick a tiny bit of ice on the climb, you still have to land with ice speeds even if it's been 2 hours and there's clearly no ice.
Second edit: was looking at correct numbers:
Lowest distance requirement flaps full with ice speeds and 5/5/5/ is 4830. EYW runway is 4801. That's at 50,000lbs. With anything resembling a normal load you're not landing.
With a dry runway things are tight, but not as bad. ISA, calm wind, flaps full, and ice accumulation you are good up to 67,500lbs (with interpolation). So light pax load, dry runway, and no alternate fuel you'll probably be ok but anything else is going to be a diversion.
I haven't looked at takeoff numbers but my guess is they're pretty tight as well. Although flaps 4 may alleviate a lot of that.
#35
Line Holder
Joined APC: May 2015
Posts: 92
The actual landing distance is significantly less than what the book shows. I'm not sure why the numbers are as inflated as they are, but they're the ones in the book so that's what we use.
The hilarious part is that we have a table for mechanical failures where you take a default distance and then apply a penalty based on what's broken. According to that table a 70,000lbs ice speed landing with a single break failure takes 4179'. According to our regular landing distance table a 70,000lbs ice speed landing requires 4930' under the same conditions.
In this situation the EYW runway wouldn't be long enough for a regular landing, but would apparently be long enough for a landing with a failed brake.
The hilarious part is that we have a table for mechanical failures where you take a default distance and then apply a penalty based on what's broken. According to that table a 70,000lbs ice speed landing with a single break failure takes 4179'. According to our regular landing distance table a 70,000lbs ice speed landing requires 4930' under the same conditions.
In this situation the EYW runway wouldn't be long enough for a regular landing, but would apparently be long enough for a landing with a failed brake.
#36
Banned
Joined APC: Jan 2016
Posts: 388
I once promised a filly I would give her a ride home in my Mercedes in exchange for some bathroom stall shenanigans. In reality I drove a white Geo Prizm with a dent in the fender.
What I'm trying to say here.. Is that you can pick up icing in the climb or decent into Key West.
What I'm trying to say here.. Is that you can pick up icing in the climb or decent into Key West.
#39
Gets Weekends Off
Joined APC: Jan 2013
Posts: 294
The actual landing distance is significantly less than what the book shows. I'm not sure why the numbers are as inflated as they are, but they're the ones in the book so that's what we use.
The hilarious part is that we have a table for mechanical failures where you take a default distance and then apply a penalty based on what's broken. According to that table a 70,000lbs ice speed landing with a single break failure takes 4179'. According to our regular landing distance table a 70,000lbs ice speed landing requires 4930' under the same conditions.
In this situation the EYW runway wouldn't be long enough for a regular landing, but would apparently be long enough for a landing with a failed brake.
The hilarious part is that we have a table for mechanical failures where you take a default distance and then apply a penalty based on what's broken. According to that table a 70,000lbs ice speed landing with a single break failure takes 4179'. According to our regular landing distance table a 70,000lbs ice speed landing requires 4930' under the same conditions.
In this situation the EYW runway wouldn't be long enough for a regular landing, but would apparently be long enough for a landing with a failed brake.
#40
Line Holder
Joined APC: Jul 2014
Posts: 35
The inflight landing tables is the minimum distance required on a runway to accept a landing. It takes into account the land and stop distance, plus 40% (FAR requirement to land and stop within 60% of available runway). The unfactored landing distance tables are the actual land and stop distance..... unfactored for inop equipment, ect. So yes, you may be able to land and stop in less than 4930 feet, but the runway length required to ACCEPT a landing is the land and stop distance, plus 40%.