Westjet CYHZ

[HiFlyChick]

From the tower tapes at liveatc.net and FlightRadar24, C-FUJR, a B-738, 172 pax plus 6 crew, no injuries, no visible damage.

Weather around the time of the accident:
CYHZ 051549Z 01016G27KT 1/2SM R14/5000FT/N SN OVC002 M00/M00 A2912 RMK ST8 SLP869

ILS to 14, tower winds 010/14G22, RVR's 3500, then 4500 then 4000

With winds of 010/14G22 (if I understand the previous post correctly, these winds were given by tower, therefore in deg mag), the tailwind component would be of 09G14 kts - that just seems like a lot of tailwind component to accept, even without a contaminated runway. Not that it can't be done, but you have to draw the line on max tailwind somewhere and it seems like 10 kts is what I've heard from most people (and what the companies I've worked for have set as a max, and we were flying light twins)

[mbav8r]

From the tower tapes at liveatc.net and FlightRadar24, C-FUJR, a B-738, 172 pax plus 6 crew, no injuries, no visible damage.

Weather around the time of the accident:
CYHZ 051549Z 01016G27KT 1/2SM R14/5000FT/N SN OVC002 M00/M00 A2912 RMK ST8 SLP869

ILS to 14, tower winds 010/14G22, RVR's 3500, then 4500 then 4000

With winds of 010/14G22 (if I understand the previous post correctly, these winds were given by tower, therefore in deg mag), the tailwind component would be of 09G14 kts - that just seems like a lot of tailwind component to accept, even without a contaminated runway. Not that it can't be done, but you have to draw the line on max tailwind somewhere and it seems like 10 kts is what I've heard from most people (and what the companies I've worked for have set as a max, and we were flying light twins)

10 knots is our max, however that is steady state wind, the gust is not factored in.

[fish4life]

Very few airplanes I know of can take more than 10kts on the tail as per the AFM, Q400 being on of them where it’s approved up to 20kts but no contam and a bunch of other restrictions.

[HiFlyChick]

From the tower tapes at liveatc.net and FlightRadar24, C-FUJR, a B-738, 172 pax plus 6 crew, no injuries, no visible damage.

Weather around the time of the accident:
CYHZ 051549Z 01016G27KT 1/2SM R14/5000FT/N SN OVC002 M00/M00 A2912 RMK ST8 SLP869

ILS to 14, tower winds 010/14G22, RVR's 3500, then 4500 then 4000

With winds of 010/14G22 (if I understand the previous post correctly, these winds were given by tower, therefore in deg mag), the tailwind component would be of 09G14 kts - that just seems like a lot of tailwind component to accept, even without a contaminated runway. Not that it can't be done, but you have to draw the line on max tailwind somewhere and it seems like 10 kts is what I've heard from most people (and what the companies I've worked for have set as a max, and we were flying light twins)

10 knots is our max, however that is steady state wind, the gust is not factored in.

Interesting that they don't factor in the gust factor... A good gust can be pretty significant

[mbav8r]

With winds of 010/14G22 (if I understand the previous post correctly, these winds were given by tower, therefore in deg mag), the tailwind component would be of 09G14 kts - that just seems like a lot of tailwind component to accept, even without a contaminated runway. Not that it can't be done, but you have to draw the line on max tailwind somewhere and it seems like 10 kts is what I've heard from most people (and what the companies I've worked for have set as a max, and we were flying light twins)

10 knots is our max, however that is steady state wind, the gust is not factored in.

Interesting that they don't factor in the gust factor... A good gust can be pretty significant

Yes, problem is, often the gust could preclude an attempt at landing.
You may or may not encounter the gust, so we use the steady state wind and if you encounter an obvious gust exceeding the limits, go around.

[lostaviator]

10 knots is our max, however that is steady state wind, the gust is not factored in.

Interesting that they don't factor in the gust factor... A good gust can be pretty significant

Yes, problem is, often the gust could preclude an attempt at landing.
You may or may not encounter the gust, so we use the steady state wind and if you encounter an obvious gust exceeding the limits, go around.

I predict a FOM amendment in our future: "and tailwind" added to "wind gusts will be accounted for in crosswind limitations" under the wind limits chart.

[Greenback]

WJ max tailwind is 10kts including gust.

[whipline]

I ran the numbers, ball parking a landing weight of 63,000kgs. Using the talpa arc (1500 feet) medium braking or 3 (best case) flap 40 and 2 engine reverse it came up with 8150 feet for max auto brake. 11 knot tailwind 12 knot crosswind.

Most NG are good for 15 knot tailwind landings. Max x-wind would be either 25/13 knots based on medium/3. Not sure how much runway was cleared for narrow or full width.

[Eric Janson]

Thanks for the replies Ladies and Gents - very interesting to read that this is not universally applied (what I was afraid of...).

With Apps and Software to calculate landing distance readily available and easy to use (and even easier to modify) there is no reason not to do this on every landing imho.

This can be implemented now - no reason to wait for legislation. I know some senior people read these forums - this needs to happen if not already in place imho.

Regarding the 10 knots tailwind limit - this comes from the manufacturer. It is possible to buy a higher limit (15 knots) which then becomes the legal limit. As far as I know this is simply a paperwork exercise.

I've seen it before with a leased fleet from various companies where one aircraft was limited to 10 knots and another of the same type had a 15 knots limitation

[Daniel Cooper]

Nobody said they didn't calculate landing distance, did they?

[HiFlyChick]

The LDA for runway 14 at YHZ is 7700 ft, but what about the fact that the touchdown point for an ILS is not at the threshold? On a light twin you can chop and drop once you're visual (within reason), but what about the big guys? With a stabilized approach following the glidepath right to the ground, the touchdown point is quite a ways down the runway. For any of the heavy metal, does this always get factored in when considering if you're gonna get stopped before the end?

[ant_321]

The LDA for runway 14 at YHZ is 7700 ft, but what about the fact that the touchdown point for an ILS is not at the threshold? On a light twin you can chop and drop once you're visual (within reason), but what about the big guys? With a stabilized approach following the glidepath right to the ground, the touchdown point is quite a ways down the runway. For any of the heavy metal, does this always get factored in when considering if you're gonna get stopped before the end?

Yes.

[HiFlyChick]

Does anyone know if this aircraft had LPV capabilities? I'm assuming that the reason why they took 14 at all was that they didn't, but maybe they thought that 200 ft ceiling made it not even worth the effort of trying the RNAV 05....

[pelmet]

Regarding the 10 knots tailwind limit - this comes from the manufacturer. It is possible to buy a higher limit (15 knots) which then becomes the legal limit. As far as I know this is simply a paperwork exercise.

My airline has decided on a maximum tailwind component for contaminated runways(which as we know includes frozen and unfrozen contaminants) and is written clearly in their governing publication…..

Zero knots. Yet diversions are extremely rare. Its probably not a bad idea.

[J31]

Does anyone know if this aircraft had LPV capabilities? I'm assuming that the reason why they took 14 at all was that they didn't, but maybe they thought that 200 ft ceiling made it not even worth the effort of trying the RNAV 05....

Rwy 5-32 was NOTAM closed. Westjet does not do LPV approaches with the 737.

[tbaylx]

Nobody said they didn't calculate landing distance, did they?

If whipline is calculating 8150' for a landing distance and the runway is 7700' long they either didn't do one or did it and failed to take into account contamination or tailwind.

In any case 7700' with a tailwind is a short runway for an -800, never mind snow on it. Should be setting off alarm bells for any -800 crew before even looking at a landing distance calculation.

[J31]

The LDA for runway 14 at YHZ is 7700 ft, but what about the fact that the touchdown point for an ILS is not at the threshold? On a light twin you can chop and drop once you're visual (within reason), but what about the big guys? With a stabilized approach following the glidepath right to the ground, the touchdown point is quite a ways down the runway. For any of the heavy metal, does this always get factored in when considering if you're gonna get stopped before the end?

A stabilized 3 degree ILS will put most aircraft touching down about 1500 from the beginning of the runway. Landing performance programs normally take that into account.

From a Navajo to Airbus 380 the accepted normal is a stabilized approach with vertical guidance all the way to touchdown. Thus chopping and dropping off an ILS is not recommended.

[HiFlyChick]

From a Navajo to Airbus 380 the accepted normal is a stabilized approach with vertical guidance all the way to touchdown. Thus chopping and dropping off an ILS is not recommended.

You're right, of course, and with the profusion of 703 accidents I shouldn't suggest it

[HiFlyChick]

Rwy 5-32 was NOTAM closed. Westjet does not do LPV approaches with the 737.

Sorry - I was thinking of the RNAV 32... There's been so many storms here lately that I can't keep track of one mess of crappy weather from another!

What's so concerning is the mindset that diversion, even under such bad conditions, isn't an option. I've heard many discussions about whether operators should upgrade to WAAS or Halifax should upgrade to 4 ILSes, and in the end, if operators don't want to do the costly upgrade then they have to be good with going elsewhere. That in itself might motivate Halifax to upgrade to ILS on 32 and 05. It might not, but then they also have to accept the loss in business.

Is this a lack of decision making skills in general, or an increase in pressure from the operators to get in? I assume that by the time someone makes captain on a 737 (or 747 in the case of last year's accident) that the employer won't be so quick to fire him based on the occasional diversion in terrible weather... or is that naivete on my part?

[daedalusx]

What's so concerning is the mindset that diversion, even under such bad conditions, isn't an option. I've heard many discussions about whether operators should upgrade to WAAS or Halifax should upgrade to 4 ILSes, and in the end, if operators don't want to do the costly upgrade then they have to be good with going elsewhere. That in itself might motivate Halifax to upgrade to ILS on 32 and 05. It might not, but then they also have to accept the loss in business.

Apparently it was looked into and it would be very challenging to put ILSes on all 4 due to terrain/obstacles.

WAAS is a pipedream for airline operators due to obvious cost/benefits.