Credit to the photographs

I would like to thank Brian Losisto (Air Canada's photographer) for always allowing me to post his pictures. (The above thrust lever pic is his). Then there is Kelly Paterson from Calgary and plane spotter "Erik" from Germany. Of course, I have lots myself. On that note, if you feel a photo(s) may be in appropriate or the content I post a bit dubious by all means send me an email. I will ratify it! That's all I ask.

...I hope you enjoy the blog...

Tuesday, November 9, 2010

Some Q and As

Lots of questions coming in behind the scenes so I thought I would post a few:
Q.I’m a 45-year-old student pilot – about 15 hours in a 172 at CYCD so far. I had a heck of a time this past season booking time off work to get lessons in – we had to cancel for weather about half the time. The TAF and local graphic forecasts are very near-term, so I’ve been looking at the surface analysis charts trying to predict what the ceiling will be a few days ahead and have had no luck. Can you offer any pointers?
A. Here's two books specific to B.C weather. The first one was produced by Environment Canada.
This second one came out last year and I scanned through it. It would be a great book as well!
You live in a unique part of Canada. Generally speaking, you need to look for "highs and and ridges" on the weather map. However, you can get pretty good weather from the outflow of the Rockies. Meaning an east wind (usually weather coming in) can mean
pretty good weather for you because of the down slope effect.
You are not the only VFR student pilot frustrated with the weather. I learned in Halifax, where good VFR conditions exist about 65-70 precent of the time.
When I flew out of Gimli, Manitoba for my commercial, it was up to 91 percent VFR.
I did take my multi IFR in Victoria in the early fall and I was actually looking for cloud.
I've only been to Nanaimo once in a friend's tail dragger. What an experience!
Happy flying!
Q. Hi Doug
In keeping with your low pressure blog.....other than during a thunderstorm, what wind conditions would cause you to be unable to land or take off. For example today (Oct 27) is crystal clear with very high winds. Would this present problems?

Here's a video of an Airbus 320 landing in the Azores. It makes for an interesting approach when you are looking at the runway through the "side window."

A. We have landing and take off crosswind limitations. For the Airbus 320 I fly, that means for landing it's 33 knots gusting to 38 knots and for landing
it's 29 knots gusting to 38 knots. If the winds are stronger than these limitations we are either looking for another runway or we are not flying.

We also have tailwind, contaminated runway, wet runway, CAT III (autoland) wind limits, etc.

But for major airports, with many runway orientations, landing and taking off are not usually an issue. bear in mind the rides can be quite bumpy due to "mechanical turbulence." Plus taxiing can be an issue especially with flying debris. One day I saw a luggage container drift by.

Q. Dear Captain Doug,

I very much enjoy your column and recently found your blog and enjoy reading that too. I have a question for you: Once upon a time, UAL used to carry the cockpit radio traffic on the PAX entertainment system. Did AC ever do such thing and will they ever consider it putting it in?
A. I think many,many years ago we offered that option. I do realize many airlines today include this neat perk. As well, many airlines
have taken this one step further and now offer a "bird's eye view" with cameras mounted on the tail, belly and nose wheel.

I am not hearing any rumour of things changing for us. I too wouldn't mind listening to the radio talk while flying as a passenger.

Maybe you could send this query to Air Canada directly?

Who knows, you may change their thinking! :)

Q. I noticed at the start of the take off roll on most aircraft ( it's not as prominent in the CRJ ) that the turbines "seem" as though they spool up, hold at a certain RPM for a couple of seconds, then continue to spool to take off setting ( I'm guessing here ) . Is this because of a "check" that happens at a certain RPM before the turbines are spooled up the rest of the way, or am I just dreaming?
and one more.....this one I haven't sent in.....
De-Icing prevents/removes ice build up on the wings prior to take off.......if you sit for too long, you have to de-ice again......what then prevents icing at altitude when traveling through cloud or descending through weather, and if it's effective at altitude, then why is it not as effective on the ground? ( i.e. no de-icing required )
A. You have good ears regarding the engine spool up. Basically we bring the engines up to about 50 percent and then to take off thrust. Some pilots accentuate the pause a little more than others so it's a little more noticeable.

We indeed get icing in cloud but most of it forms on the leading edge of the wing. We have deicing capability along the leading edge where most of this
airframe ice accretes. Warm air is "bled" from the engines along the leading edges. We also have engine deicing where warm air is moved along the intake of the engine, engine igniters and heated windshields. This type of icing happens about 75 percent of the time. Sometimes ice forms further from the leading edge and this can be an issue. Usually a change in altitude can ratify things. There are many variables which cause airframe icing.

Again, the aircraft deicing is effective only for the leading edges. Whereas icing and snow accretion on the ground affects the entire airplane, hence, deicing required.

Q. I have a utility that calculates Vspeeds for the A320 and a lot of other planes (Topcat is the name). The designers of the problem has gotten the real Vspeed information from a real ACM for the A320. It calculates the weight and basically everything your ACARs inside the airplane can do that relates to it. Now, when I put all the information in and everything like that and hit calculate, it will give me the trim, weather information ( Crosswind, headwind component ) , Anti effects and everything like that. It also gives me the V1 speeds. I have seen a Captain print the Vspeed information out before but he never really explained how he picks which one. I seen and see on my program that there can be a lot of selection for that weight and runway, or there can be 3 - 4. A picture is included to really explain what I am asking

A. We do things a little differently. We input data into the datalink: Our weight, runway, flap setting, ambient temperature, pressure, engine anti-ice on, etc.
Out comes a chart like this below:
So if our take off weight is actually 71.7 tonnes we round up to 72 tonnes.

The speeds are 155-155-156 and we can "flex" to 33 degrees. That's at zero wind or at least below 10 knots sustained.

Hope this helps.

Captain Doug

A320-211 FIN 201
TORA 9697 FT
PRESS : 29.74 WING A/I : OFF


0 TOGA 75.9 161-161-163
TOGA 72.0 146-146-148
31 72.6 152-152-154
33 72.0 155-155-156
34 71.4 154-154-155

10 TOGA 76.8 164-164-165
TOGA 72.0 146-146-148
33 72.6 155-155-156
35 72.0 157-157-158
36 71.4 156-156-157



Adam aka "The Winnipeger" said...

WOW! That Crosswind Approach was crazy!!!!! Have you ever done one like that Doug??

The Winnipeger,

Anonymous said...

Captain Doug,

Great information, thanks for sharing it. You've got some readers with some great questions!

YYC Dispatcher

Scote1992 said...

What does FLEX mean? I fly an A320 sim on my computer and I know that it always puts in a default for that number, but what is it actually?

Scote1992 said...

Oh, by the way, I'm going to solo for the first time tomorrow in a C152. I have 6.7 hours right now.

From the Flight Deck said...

YYC Dispatcher. Yes, you guys are an inquisitive bunch...but this is good!

From the Flight Deck said...


Flex is an Airbus term but other manufacturers use the concept as well.

Many assume an airliner uses full thrust for take off. Not so.

In order to save wear and tear, and provided conditions are met, we can take off with less than several full thrust. What we do is sort of trick the engine. We tell the engine it's really warm outside.
Say 50C. Warmer air is less dense so the engine will produce less thrust. This is our "flex" temperature
take off setting.

From the Flight Deck said...


You are going solo in just 6.7 hours??? Wow, you must be learning an incredible amount from this blog! lol

Good for you!!!

From the Flight Deck said...

I've been in some interesting approaches and take offs but that one seems to take the cake. :)

Chris Gardner said...

I have been on flights landing in YYT that can be quite bouncy now and then. Exspecally when you do have strong westerys and the flight have to make a hard left turn before making a landing on runway 29.Besides I have seen videos flights landing at the old Hong Kong airport it makes a interesting watch.

From the Flight Deck said...

Chris. I agree about the "bouncy" flights while flying into CYYT.

Yes, the "checkerboard approach" followed by a huge crosswind landing into Hong Kong proved interesting.

I only did the approach in the simulator.

By the time I flew there they built a new airport for me and made it a lot easier. lol

Captain Doug

carlton said...

"But for major airports, with many runway orientations, landing and taking off are not usually an issue".

I guess London's Heathrow and Gatwick may occasionally suffer when cross wind gales gust across Heathrow's two parallel runways and Gatwicks single runway. I have never heared of Heathrow closing operations because of cross wind though.