Mexico Incident

[DEFCON]

It'll be interesting to learn how this near CFIT event occurred. Regardless, it is comforting to see that the crew responded to the alert without trying to determine why it activated.

From the Av Herald:

"Incident: Canada Rouge B763 near Huatulco on Jan 29th 2018, EGPWS terrain warning prevents CFIT

By Simon Hradecky, created Wednesday, Feb 7th 2018 21:15Z, last updated Wednesday, Feb 7th 2018 21:38Z An Air Canada Rouge Boeing 767-300, registration C-GHLU performing flight RV-1893 from Calgary,AB (Canada) to Huatulco (Mexico) with 250 passengers and 9 crew, was in level flight at 16,000 feet about 33nm north of Huatulco in non-radar environment, when air traffic control cleared the flight to descend to 6000 feet MSL at pilot's discretion. About 30nm north of the aerodrome the crew initiated the descent, about a minute later at 11,800 feet MSL the crew received an EGPWS "Caution Terrain" aural warning. The crew climbed the aircraft back to 13,500 feet MSL and continued to Huatulco before commencing the descent and landing safely."

http://avherald.com/h?article=4b4a3896&opt=0

 

 

 

 

 

[blues deville]

Used to do HUX when it first opened as a new destination back in the early 90’s. You have to be very careful about MEA’s descending into the area and be prepared to use lots of speed brake once you’re clear of the coastal mountain range. 

[Kip Powick]

Used to do a lot of flying into weird destinations that had  few ground based  nav aids with  the trusty CV-580 and CC-130... In those cases we always made sure we had a topographical map with the route drawn on it.

Would rather do a "spiral" descent than impacting a cumulus granite.

[J.O.]

The highest terrain in that area is directly north of the airport with a maximum terrain height of 13,200 ft. If the report is accurate, issuing a clearance to 6,000 ft when the aircraft is in that sector would seem like a pretty huge screw-up.

[DEFCON]

I agree, the clearance is an invitation to disaster, especially in a non-radar environment and really should be reconsidered procedurally imo.

On the other hand, the clearance to 6K is reported to have also included the phrase; 'at pilot's discretion', which as you know means the pilot is clear to descend at his convenience, but remains responsible to respect published obstacle clearance altitudes.

 

 

   

[Kip Powick]

6 hours ago, DEFCON said:

hen air traffic control cleared the flight to descend to 6000 feet MSL at pilot's discretion

 

 

33 minutes ago, J.O. said:

issuing a clearance to 6,000 ft when the aircraft is in that sector would seem like a pretty huge screw-up.

I don't think so, crew should have been aware of MSA/MOCA...I don't have a chart but I would think those altitudes are clearly marked.

[j.k.]

I think it gets lost a bit on pilots used to being "handled" into larger airports. Especially if they don't have a background flying in mountainous areas.

But flying into secondary/smaller airports without a terminal environment it has to go back to IFR basics... "What's my minimum altitude here?"

It's not just in Mexico or Brazil either that they will set you up like this...

I remember years back I was on an airway at 10,000', part way along my route a YVR centre controller cleared me direct to destination through MORAs in the range of 15,600', 12,800', etc. while I was IMC on an airway at 10,000'... "Uhhh... no thanks..." 

Terrain is your responsibility unless you are being vectored... Even then...

[DEFCON]

What ever happened to the route & regional qualification programs that once existed? Were they a casualty of Deregulation and cost control initiatives?

 

 

[blues deville]

4 hours ago, J.O. said:

The highest terrain in that area is directly north of the airport with a maximum terrain height of 13,200 ft. If the report is accurate, issuing a clearance to 6,000 ft when the aircraft is in that sector would seem like a pretty huge screw-up.

None radar area so ATC normally asks for DME from HUX VOR before clearance to a lower altitude. Further descent requires waiting until overhead the VOR and you cannot use VNAV. Sector altitudes are clearly marked and one turn once overhead the VOR descending generally puts you on the path as there are plenty of track miles to lose altitude before the runway.

Good thing the GPWS wasn’t U/S that night. 

[J.O.]

3 hours ago, Kip Powick said:

I don't think so, crew should have been aware of MSA/MOCA...I don't have a chart but I would think those altitudes are clearly marked.

I stand by what I said. You don't set people up for failures if you want success.

[blues deville]

5 hours ago, J.O. said:

I stand by what I said. You don't set people up for failures if you want success.

Might be considered a “gotcha” by some but really no different than any other descent where the pilot is responsible for terrain clearance. That’s a long flight from anywhere in Canada and generally a night time arrival in the holiday package world. The high terrain part is the last 30 mins but you need to stay alert. 

[Kip Powick]

24 minutes ago, J.O. said:

I stand by what I said. You don't set people up for failures if you want success.

Let's just agree to disagree ......but I think your thinking/comment  is in the minority in this thread

(See..... Blues / JK / DEFCON)

[Moon The Loon]

On 2/9/2018 at 10:14 AM, J.O. said:

...would seem like a pretty huge screw-up.

By Mexican ATC??? Like the time the LearJet was launched off the westbound runway at PVR while we were 5 miles final, eastbound??

[Kip Powick]

 

If it was my first time there and was NOT VFR, with good visual reference to the terrain, I think I would have done a shuttle descent over the VOR..... 

I find the numbers a bit scary to just start down in the "gloom". 

[DEFCON]

How do these sorts disagreements get underway? There's no doubt, the clearance sets a trap for anyone that's not paying proper attention and the PIC is ultimately responsible for obstacle clearance regardless, which makes both positions correct.

 

 

 

 

[blues deville]

1 hour ago, Kip Powick said:

 

If it was my first time there and was NOT VFR, with good visual reference to the terrain, I think I would have done a shuttle descent over the VOR.

That’s exactly how to do it. One descending turn over the VOR and then leave it outbound on the approach monitoring your path. 

[j.k.]

"You're cleared an approach" 

How low can you go? 

Whose responsibility is it?

I understand how these guys made a mistake, but it's IFR 101.