Late notice windshear

[BobDDuck]

Set up:

Flying into LGA, the Expressway Visual to 31. About 5 in the evening, clear blue sky day. ATIS has the winds on the ground as 330@6. On the arrival there was a layer of light chop at about 5000 but other then that it was completely smooth. Landing weight is right around max and the speed is bugged for flaps 45 (full) + 5 knots per the book. Number one for the runway with traffic just rolling out and traffic launching on the crossing runway.

Turning modified base (off the freeway and over Flushing Meadow's Park) tower reports low level windshear. A loss of 25 knots at 1 mile and a loss of 15 knots at 1/2 mile. Surface winds are 340@9.

The previous landing traffic never said anything.

You are now at 1300 feet descending and turning base to final.

What do you do?

[jtrain609]

What are the winds on your FMS dealie telling you? If they're not 34 knots, then something is screwy with ATC's equipment.

[BobDDuck]

FMS winds are showing 310@9.

BUT... FMS winds are very delayed and not very accurate at all.

I had a for real 30 knot increase at about 500 feet going into CLT. The winds on the FMS never changed until we were climbing through 2000 feet going around.

[jtrain609]

Is the plane gettin' it's ass kicked? Are you hand flying at this point? At that altitude you're about to get into the predicted wind sheer and the plane is going to be telling you about it real soon.

(See, all this time hand flying DOES teach you a few things! )

[Baronman]

A 25 kt loss at 1 mile would definetely catch my attention. We're talking about 300'AGL at 1 mile, not very high. Minus 10, minus 15 ok.... Minus 25 knots I think I'm goin around, especially if I'm the first one to land since the issuance. If the alert was 10 minutes old with a couple landings and PIREPS ahead of me, that's a different story. God forbid something bad happens, "So you decided to land even though a 25kt loss was reported at 300'?"

[Louie1975]

Hey, as someone who grew up in Queens(up until 10 yrs old I was under the extended rwy centerline of RWY 4!), LGA is definitely one of the reasons for my pursuing piloting(along with Air Jamaica, buts that's another story).

Let me ask, when a flight crew is paired to LGA and both have never been on the Expressway Visual, are those landmarks easy to figure out? I mean, I have seen those airplanes make that turn over Shea 100s of times, and it seems very precise, but I would think that if you've never done it it might be hard to figure out for the first time at 140 plus knots. Is this programmed in the FMS?

And Bob what did you do? And what type A/C do you fly?

[BobDDuck]

It's not to bad of an approach. LGA is a special quals airport anyways so one pilot must have been there in the past 6 months or have reviewed a "special airports" book that is supposed to be in every crew room. The first few times flying the visual is a little interesting, but a plane is a plane and most of them turn when you tell them to. I'd bee interesting to hear how Denny found the transition from a CRJ to a Mad Dog down the expressway.

There is no real way to load it into the FMS, although you can sort of make up an approach by building a course off of DIALS (the "initial" fix) to the intersection of the final approach course. At least it gives you some vertical guidance, not to mention there is probably the worlds biggest VASI on 31 helping things along.

[calcapt]

Bad winds in LGA seem to be the norm rather than the exception. In the situation you described Bob, I would bug and fly ref plus 20 and proceed. Do not chase airspeed and insure that the airplane is landed in the first 1000 feet of the runway. If unacceptable windshear conditions occur, go around and figure out plan B. If we waited for the winds at LGA to calm down to land, we may be waiting for days. JMHO.

By the way, I have had this exact LGA scenario more times than I care to remember. Never a dull moment there in Queens!

[Alchemy]

The PIREP or lack thereof from the preceeding traffic seems to be the biggest green light in this case. I would continue, but of course would go around if the GPWS detected windshear.

In addition, per CFM guidance, I would

-Consider landing with a reduced flap setting, assuming available landing distance is adequate.
-Avoid large thrust reductions or trim changes in response to sudden airspeed fluctuations
-Consider use of the autopilot to facilitate closer monitoring of vertical speed and airspeed indications
-Add the appropriate gust factor to the ref and target speeds
-Stabilize the approach no later than 1000 AGL
-Execute a go around if stabilized approach parameters are exceeded, or if vertical speed, altitude, or glideslope deviations indications depart significantly from what would normally be expected
-Pilot monitoring should call out such deviations as they occur
-Closely monitor flight director commands and crosscheck them with flightpath indications.

[jtrain609]

Erm...what ever happened to kicking off george, grabbing onto the plane and then looking outside to see if things are going to ####? I mean you can see pretty quickly that you're developing a sink rate, probably faster than it's going to register on your VSI (even if it is an IVSI).

Or have I been hand flying too long?

[Alchemy]

Originally Posted by jtrain609

Erm...what ever happened to kicking off george, grabbing onto the plane and then looking outside to see if things are going to ####? I mean you can see pretty quickly that you're developing a sink rate, probably faster than it's going to register on your VSI (even if it is an IVSI).

Or have I been hand flying too long?

Definitely been hand flying too long

But seriously, I do think that hand flying would probably be easier in this case, especially since it's a visual. However, I would argue that in the event of a go around, having the autopilot coupled will greatly reduce the workload, especially in a place like LGA. The liklihood of the go-around is also the primary reason to use a reduced flap setting (it would minimize altitude loss and re-configuration time during the go around). However in this particular secenario it's probably too late to be digging through the books looking up new speeds and req'd landing distances for the new flap setting. I also have agree with "the book" in thinking that it's much easier to notice trends when the autopilot is engaged than when you're hand flying. It's always easier to sit back and critique the autopilot than it is to critique yourself on something while you're doing it. In addition, I don't see how having the autopilot engaged is going to prevent you from visually identifying any excessive sink rate, same as you could if you were hand-flying.

Also, in a non-autothrottle equipped airplane having the autopilot engaged allows you to focus more carefully on power settings....you could call it tunnel vision but it's pretty easy to lose track of just how much thrust you're commanding when you're focusing on a visual maneuver and cross-reference your primary flight instruments.

Hope I don't sound like an RJ-driving sissy autopilot addict. To be honest I would probably *not* use the autopilot in this situation simply because I rarely use it below 3000 AGL, especially on visual approachs, but I could certainly see the wisdom in turning it on if someone chose to do that.

Good discussion. Just my 2 cents.

[jtrain609]

Naw not at all, I just don't know how to use the damned things to be honest with you. I've got such a limited experience with autopilots and flight directors that in most situations I look at how you guys would use an autopilot and think, "So ahh...I mean we do that crap with our hands all the time, isn't it more intuitive to do what you've been trained to do and just fly the thing yourself?"

But for me it goes a little further than that and into any automation at this point. We had an essential bus kick out on us the other night in a King Air which dumped the cabin, we lose the boots, all the instrument lighting, an inverter, blah blah blah. Basically half the airplane dies. We declare and start setting up for the VOR approach back into Oakland and I try to plug it into the GPS and after about 10 seconds I'm like, "Huh, this thing doesn't work like a 430...whatever, I know that we're on a left downwind on vectors, I don't need this thing" and happily go back to working on monitoring the aircraft to make sure the captain doesn't make any wrong moves (the AP and FD were on the same bus, BTW, so they were also useless at this point).

So when I see a crappy situation happening, I start cutting away technology even when I have it, but when things start going bad for you guys you're trained to start turning it on so you don't have to actually worry about flying the plane and you can put more attention into watching all the mass of systems in your aircraft. Just a different training philosophy for different equipment types.

[BobDDuck]

Originally Posted by jtrain609

Erm...what ever happened to kicking off george, grabbing onto the plane and then looking outside to see if things are going to ####? I mean you can see pretty quickly that you're developing a sink rate, probably faster than it's going to register on your VSI (even if it is an IVSI).

Or have I been hand flying too long?

The captain was already hand flying. It's a moot point really though. What I was getting at was would you continue into a situation where tower was reporting a VERY nasty shear if the only evidence of it was from a LLWS reporting system and every other indication (current flight conditions, aircraft in front and surface winds) indicated that there was no shear.

We continued after quickly re briefing a windshear escape go around. It was a perfectly smooth approach until the captain planted it on the runway.


Alchemy, I completely get what you are saying, but here's a case where a 250 hour procedurally smart pilot would be in trouble.

Originally Posted by Alchemy

In addition, per CFM guidance, I would

-Consider landing with a reduced flap setting, assuming available landing distance is adequate.
CRJ only has full flaps. Stupid super critical wing.
-Avoid large thrust reductions or trim changes in response to sudden airspeed fluctuations
Fair enough.
-Consider use of the autopilot to facilitate closer monitoring of vertical speed and airspeed indications
Hard to use the autopilot when on the Expressway Visual.
-Add the appropriate gust factor to the ref and target speeds
Surface winds are 9 knots. No gusts.
-Stabilize the approach no later than 1000 AGL
The approach turns final around 1/2 mile and at 500 or so feet.
-Execute a go around if stabilized approach parameters are exceeded, or if vertical speed, altitude, or glideslope deviations indications depart significantly from what would normally be expected
Yep.
-Pilot monitoring should call out such deviations as they occur
SOP and a good idea.
-Closely monitor flight director commands and crosscheck them with flightpath indications.
No flight director when turning and banking on the approach.

[Kingairer]

Id just straightin up and fly the thing right.

[EDUC8-or]

Originally Posted by jtrain609

Erm...what ever happened to kicking off george, grabbing onto the plane and then looking outside to see if things are going to ####? I mean you can see pretty quickly that you're developing a sink rate, probably faster than it's going to register on your VSI (even if it is an IVSI).

Or have I been hand flying too long?

Believe it or not, it's a WHOLE lot easier to hand fly approaches like this and the River Visual 19 into DCA. The autopilot just can't react quickly enough and you would have to fumble around with the automation way too much.