Good News for SWA Pilots!!!??? Breaking News?

[Rally]

Quit speculating Rally! Again, you are making an assumption that perhaps they landed too far down or too fast. All indications point at the fact that they were right where they needed to be. It's unprofessional to make such assumptions and second guess anyone here. One last thing Rally, I hope that you do understand that this could have happened to anyone of us!

Was'nt trying to speculate I think its highly likely that it is either all or partially NOT the pilots fault. But this aircraft did'nt just overrun a little it over ran ALOT. Probably 1000-2000 feet right? Again not trying to point fingers just trying to understand.

 

[Flystr8]

Reversers or not should'nt the -700 be able to stop in that length of runway with that amount of snow UNLESS they were too fast or too long?

It was reported that the aircraft picked up a tailwind on final approach. Not sure how much that will factor into the outcome but it was an issue.

 

[Oakum_Boy]

Landing data two engines is based on no reverse, takeoff data the same. The only time reverse comes into play is landing with one engine, and stopping with a failure prior to V1.

This is wrong. That data is for a dry runway. When you have a contaminate on the runway, all bets are off. You must use actual landing distance data for a contaminated runway. If your airline or manufacturer does not publish that information, look out. You're gonna be dissapointed in that "no thrust reverse, factored landing distance" calculation you did at the gate. See ya-

 

[EagleRJ]

Nice post concerning required aircraft operating characteristics, but unless you're an experimental test pilot participating in an aircraft certification program, you're reading the wrong regulation. Note the the title: Part 25: AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES. You need to be reading Part 121: Operating Requirements: Domestic, Flag and Supplemental Operations.

I included the hyperlink so you can read Section 25.1 Applicability. Part 25 has nothing to do with operating the aircraft after it has earned it's Airworthiness Certificate unless you are working on an Supplemental Type Certificate.

GV

Part 25 is not of consequence only to test pilots during certification.

If you look in the limitations section of a transport category aircraft's AOH, I suspect you will see Part 25 mentioned as a basis for the data. Part 25 regulations are used along with Part 121 regulations in governing the daily operation of an airliner.

A good way to think about it is: Part 121 tells you how much runway is required, and Part 25 tells you how much runway is actually used.

 

[satpak77]

uh...not so good news...

while not official POH guidance, nonetheless....

http://www.b737.org.uk/limitations.htm

"No tailwind component allowed on contaminated runways"

this is independent of any TR problems or other stuff

don't know if this applies to the 737-700....came across it when I was reading up on 737 performance data

 

[TR4A]

while not official POH guidance, nonetheless....

http://www.b737.org.uk/limitations.htm

"No tailwind component allowed on contaminated runways"

this is independent of any TR problems or other stuff

don't know if this applies to the 737-700....came across it when I was reading up on 737 performance data

This is posted on that site:

"Note: Not all limitations given here are AFM"

 

[satpak77]

This is posted on that site:

"Note: Not all limitations given here are AFM"

agree...just posting what I found for an FWIW type thing

 

[9GClub]

So we're tossing out reverser data for a dry runway but including it for a wet one huh? Why do we wanna add the reverser variable to an already full wet runway equation? This is SOP?

So these guys are expected to bleed off 120KT on a [6522'-1000'=] 5522' contaminated runway with no EMAS, a tailwind, and a better-be-functioning TR setup. No thanks.

 

[satpak77]

So we're tossing out reverser data for a dry runway but including it for a wet one huh? Why do we wanna add the reverser variable to an already full wet runway equation? This is SOP?

So these guys are expected to bleed off 120KT on a [6522'-1000'=] 5522' contaminated runway with no EMAS, a tailwind, and a better-be-functioning TR setup. No thanks.

dude when you solo your 152 get back to us.....

 

[Oakum_Boy]

So we're tossing out reverser data for a dry runway but including it for a wet one huh? Why do we wanna add the reverser variable to an already full wet runway equation? This is SOP?

So these guys are expected to bleed off 120KT on a [6522'-1000'=] 5522' contaminated runway with no EMAS, a tailwind, and a better-be-functioning TR setup. No thanks.

Yes, absolutely! Thrust reversers have negligible effect on a dry runway!
Surprised? Well, hopefully you're not equally surprised that on a wet runway, the coefficient of friction (mu) is diminished. Brakes are effective, but not nearly so as thrust reversers. As friction decreases, so does the effectiveness of the brakes. Therefore, thrust reverse becomes more effective than brakes!

Wet and contaminated landing distances are calculated using thrust reverse as well as brakes. It may seem illogical, but you have to consider more complex issues on transport certified aircraft.

Lesson over.

 

[ultrarunner]

Does SWA FOM authorize landing on contaminated runways with a twc?

 

[LarryinTN]

[6522'-1000'=] 5522' contaminated runway

What is 6522-1000? The runway has a displaced threshold leaving only 5826' available for landing. Glide slope hits the runway with a little more than 4900' remaining.

 

[Dumbledore]

Yes, absolutely! Thrust reversers have negligible effect on a dry runway!

No! ABSOLUTELY untrue statement as an absolute. The effectiveness of reverse thrust is specific to the aircraft upon which the reversers are installed.

Reverse is all but irrelevant on a Falcon 50/900 - only one bucket. Reverse is frighteningly effective on a GII/III!

 

[Dumbledore]

A good way to think about it is: Part 121 tells you how much runway is required, and Part 25 tells you how much runway is actually used.

This is a really BAD way to think of it. Part 25 has ABSOLUTELY NOTHING to do with the daily operation of an aircraft of any kind.

Part 25 deals with certification of an aircraft that a manufacturer wants to sell to its customers. It is a list of things the manufacturer must do in constructing the plane, the performance goals that must be met by that plane once it enters flight testing, and the data that must be documented and made available to the pilots who will operate the plane once the aircraft is certified.

The only substantive connection between Part 121 and Part 25 is that Part 121 requires the use of Part 25 certified aircraft in order to obtain operations specifications and a certificate. The major reason? Part 25 guarantees that the plane will climb if the most critical powerplant suddenly becomes inoperative at or after V1.

 

[pilotpat]

While I certainly don't want to offend anyone, I keep reading and hearing that the landing was "smooth". I just landed my Falcon 20 in blowing snow during the same storm when it hit the northeast on Friday. AND on a runway that's 4840'. Understand, my airplane only weighed 26,000 #'s (I have no idea 737 data), but by landing "firm", I was able to deploy the TR's without any hesitation and barely touch the brakes (didn't want to crank them up on a contaminated rwy), leaving about 1000' remaining. I can tell you when I give the customer a smooth landing, the squat switch doesn't always engage immediately. I don't want to speculate on another pilot's technique, however I am saying what my experience has shown me. During the winter in the northeast, sometimes an ugly "carrier" landing is all I can give 'em if the runway precludes the much sought after grease.

 

[EagleRJ]

This is a really BAD way to think of it. Part 25 has ABSOLUTELY NOTHING to do with the daily operation of an aircraft of any kind.

I see. So what you're telling me is that I can land at Ref +30 using takeoff flaps, and use only reverse to save the brakes, and I'll use exactly the amount of runway it states in the performance charts?

Where do you think your takeoff and landing data comes from?

 

[Lampshade]

I had a source tell me that the reversers are included on the 737-700 landing data but not on the previous versions of the 737. Can anybody who flys the 737-700 nail that down. All I know is Airbus and they are not included in landing data.

 

[Oakum_Boy]

I had a source tell me that the reversers are included on the 737-700 landing data but not on the previous versions of the 737. Can anybody who flys the 737-700 nail that down. All I know is Airbus and they are not included in landing data.

Exactly which "landing data" are you talking about? Factored or actual?

 

[Oakum_Boy]

No! ABSOLUTELY untrue statement as an absolute. The effectiveness of reverse thrust is specific to the aircraft upon which the reversers are installed.

Reverse is all but irrelevant on a Falcon 50/900 - only one bucket. Reverse is frighteningly effective on a GII/III!

Not on a dry runway, I'm afraid. You're saying that two buckets are more effective than one? That isn't rocket science. My point is that on a dry runway, thrust reverse has relatively little importance when comared to a slippery runway. One bucket or four, it is all relative-

 

[Lampshade]

Exactly which "landing data" are you talking about? Factored or actual?

You crack me up. Why don't you answer both if you know? Or better yet just the important one.