


Q: Some airplanes leave a contrail and some do not. Why is this?
Rebecca Pekilis
Toronto
Contrails, or condensation trails, are water vapour spewed from the jet engine’s exhaust. Because of frigid outside temperatures, about -57 degrees Celsius, this moisture immediately freezes, forming ice crystals. Sometimes the air is very dry, so these contrails evaporate quickly. However, when the air is moist – typically when a weather system is moving in – these contrails take much longer to disperse and can actually be a precursor to changes in the weather.
Q: Why are aircraft windows so small?
Kerry Smith
Toronto
Windows are built small and round to withstand the frequent cycles of pressurization. A round window withstands pressure better than a square one. Yet windows in general are getting much bigger on airliners and private jets thanks to state-of-the-art materials and new manufacturing techniques. But wait until the Boeing 787 Dreamliner shows up in a couple of years! The windows will be 65 percent larger than industry standard. Plus, they will darken at the push of a button, making window shades passé!
Q: How are flight numbers derived?
Giulia DeRosa
Ottawa
Nearly 700 daily flight numbers get airborne! The first digit generally dictates the destination: 0 is for flights to Asia and South America, 1 represents a Canadian transcontinental flight, 2 is for Western Canada flights, 3 generally designates flights to the U.S. East Coast, 4 is Rapidair® service, 5 is for flights to the U.S. Midwest and West Coast, 6 is for flights to Canada’s East Coast, 7 is for LaGuardia and the U.S. West Coast, 8 is for European flights, while 9 is mainly for Florida and Caribbean flights. Flights south and east end in an even number, and west and north flights have an odd number.
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!!!!!! HAPPY NEW YEAR EVERYBODY !!!!!!
33 comments:
Happy New Year Captain Doug and all!
Funny you should post a question about contrails....yesterday, while downhill skiing with my oldest daughter, an aircraft was flying overhead and I noticed something very odd.....at the same time my daughter says " that plane looks like it only has 3 engines running! " She noticed too! I was not "balanced" either like a tri engine plane would be....clearly it was two engines on the left wing, and one outboard engine on the right wing!
Also, along with the contrail question.... when you see a contrail push up and down instead of staying straight until it breaks up....would this be a sign this particular flight was going through turbulence at the time???......and yes the heading of the plane change abruptly after with a hard right turn!
Haven't had a chance to read the latest posts...busy holiday!
Happy New Year and Flying!
CAT III Approach
^ It was probably a three engine jet/two engine jet due to a optical illusion. The only plane's technically legal and able to fly with a different number of engines on a wing are the 747 series and L-1011. However, the engine isn't running but rather " taking a ride " and being transported back to a base or a plane in need on the wing and wind milling in the air.
PIC : (5) Engines
http://eu.airliners.net/aviation-photos/middle/9/2/4/0289429.jpg
PIC : (3) Engines
http://www.airliners.net/photo/American-International-Airways/Boeing-747-132%28SF%29/0224038/L/
PIC ( L-1011 ) : (4) Engines
http://www.airliners.net/photo/Gulf-Air/Lockheed-L-1011-385-1-15-TriStar/0011922/L/
Also note that British Airways flying from West to East across the Atlantic on the 747's have blissfully flown a 747 across the Atlantic after an engine failure in order to preserve profits.
CAT III Approach. Happy New Year!
Like Daniel mentioned some aircraft can carry an extra engine under the wing. They are either ferrying it to a maintenance base or sending an engine to rescue an aircraft.
ButI'm certain you can't see the engines from the ground up to flight level, just the emanating contrails. Something was going on. Maybe they shut down an engine? But I haven't heard anything in the news.
Yes, contrails give an indication of ride conditions. I amended my post to include one of my pictures.
(This website only allows the pictures to be posted at the beginning. It's next to impossible to move the pictures around) This same picture is seen on page 86 in my book.
Also some cloud at altitude appears with vertical hooks indicative of a rough ride.
Captain Doug
Daniel. Thanks for coming up with the links! Great pictures. Passengers are amazed to see an extra engine sitting out on the wing.
Captain Doug and Daniel,
Yes...I see in my post that I did indeed say engines, but should have said contrails! The aircraft was high so it would for sure be impossible to actually see engines! Sorry about the wording. I ruled out optical illusion because the flight path was directly over my head and a perfectly clear day. There was clearly an engine shutdown. One of those times that I should have taken a picture!!!!
There were some nasty vertical hooks prior to the right turn as well! Thanks for the pics Daniel and Doug for the response!
CAT III Approach
Happy New Year, Captain Doug and all! 2011 may well be come the decade of recovery for air carriers - and the folks that run the pointy ends of the beasts.
I've enjoyed the recent contrails discussion and note: From the ground it is often easy to see left wing and right wing, but counding the burning engines one each side might be tough. I think it is also 'possible' that the aircrafe really was burning/turning only three of four. It is rare, but it happens. I have to wonder, what is the author's point?
On other subjects, (From private email) Just being 'nice' to junior colleagues and other professional associates is just the way to do it! It costs nothing and it makes the working environment oh so much more pleasant. The Captain sets the tone and a warm one works. We are on the same page and nuff said.
Expanding my reading a bit, I read through several popular FA blogs. What a difference!! As a general thing, the FAs enjoy their work, have lots of fun, but spend too muc time trashing their PAX. With some I also note that many/most of today's FAs are mature folks, average age is pushing 40 or more. This is GOOD! FAs are cabin safety agents, first. The rest of their business is secondary and they DO know the difference. Experienced PAX also appreciate the difference and they NEVER fail to comply with announcements or instructions. The others simply should not fly.
With the season's weather, I feel for the folks at the pointy end! Go or Cancel? It is a difficult choice for ALL concerned. A cancellation will annoy at least 50% of the PAX, but an end diversion will annoy ALL of them. None are headed for the divert location.
Capt. Doug: Do you ever discuss that with dispatch/operations folks? Have you ever refused a leg, based on destination weather, when OPS thought t he flight was OK? Within your obvious limits, please flesh it out a bit. How are these choices made?
Thanks and Happy New Year.
-Craig
Sorry, A P.S. The lead pix on the most current post, some 'bumps' in the contrails and while in 'clear' air is just one more reason for PAX to keep their belts ON, if loose, when seated. Been there... and I do. The drivers who ride at the fron end of that flying tube ALWAYS have theirs on, so there must be a reason (duh?).
The few moments of ride, as depicted in today's lead picture must have been interesting. Buckle up folks and stay that way, short of some special mission. The drivers intend to get home alive and healthy and they ALWAYS have theirs on. Why not you too?
**I appreciate your support of prospective pilots, Capt.Doug. Most of it is done via back channels, but I know that you are enouraging the youngsters that contact you. One of these days, you may see a couple of them on your 787 deck. It is part of being nice.
-Craig
HI Craig. Happy New Year!
You made some valid points - again!
As far as discussion with flight dispatch most certainly. For me about 90 precent of flight plans go unchallenged.
I raise an eyebrow when they are planing me too close to convective activity when heading to Florida or the Caribbean.
They can expect a call. I don't usually challenge them on fuel, but I know many do.
Last winter they were going to send me with a full passenger load to Newfoundland in a winter storm. My alternate would be all the way back to Toronto.
After a solid discussion they finally decided to cancel the flight. You can only challenge mother nature to a certain degree.
Overall, I find our flight dispatch does an amazing job. The accuracy of the fuel burn is mind boggling, but much of it has to with the accuracy
of the upper winds depicted from the weatherman.
I also had an issue where they planned me with an airplane with one air conditioning pack to the Caribbean ladened with "thunderbumpers."
One pack restricts you to 31,500, and with thunderstorms, the higher the better as far as picking around them. They found me another plane.
Again, through mutual discussion weather and mechanical situations usually get easily resolved.
I'm off to Puerto Vallarta and back tomorrow. It will be another new airport added to the list.
Captain Doug
Craig. I responded to your last comment, but I noticed it didn't make the blog. I'm perturbed.
However, I noticed this comment did make it. Weird.
Yes, that's why the seat belt is mandatory while seated. A few years ago around Christmas time an American carrier ran into severe turbulence off the coast of Japan. One person was killed. Since then, the law is to stay buckled up while seated.
Yes, this blog is a lot about encouragement. And as the saying goes, "be nice to the people going up the ladder, because they may the same people you see going down the ladder.
Ahhh the B787 flight deck...the proverbial carrot. :)
Captain Doug
For some reason this comment did not come through.
Posted by Craig.
Happy New Year, Captain Doug and all! 2011 may well be come the decade of recovery for air carriers - and the folks that run the pointy ends of the beasts.
I've enjoyed the recent contrails discussion and note: From the ground it is often easy to see left wing and right wing, but counding the burning engines one each side might be tough. I think it is also 'possible' that the aircrafe really was burning/turning only three of four. It is rare, but it happens. I have to wonder, what is the author's point?
On other subjects, (From private email) Just being 'nice' to junior colleagues and other professional associates is just the way to do it! It costs nothing and it makes the working environment oh so much more pleasant. The Captain sets the tone and a warm one works. We are on the same page and nuff said.
Expanding my reading a bit, I read through several popular FA blogs. What a difference!! As a general thing, the FAs enjoy their work, have lots of fun, but spend too muc time trashing their PAX. With some I also note that many/most of today's FAs are mature folks, average age is pushing 40 or more. This is GOOD! FAs are cabin safety agents, first. The rest of their business is secondary and they DO know the difference. Experienced PAX also appreciate the difference and they NEVER fail to comply with announcements or instructions. The others simply should not fly.
With the season's weather, I feel for the folks at the pointy end! Go or Cancel? It is a difficult choice for ALL concerned. A cancellation will annoy at least 50% of the PAX, but an end diversion will annoy ALL of them. None are headed for the divert location.
Capt. Doug: Do you ever discuss that with dispatch/operations folks? Have you ever refused a leg, based on destination weather, when OPS thought t he flight was OK? Within your obvious limits, please flesh it out a bit. How are these choices made?
Thanks and Happy New Year.
-Craig
Craig. I figured it out. Your post was TOO BIG!!!
I truncated it.
Hope this works for you. :)
Doug
Puerto Vallarta ... Amazing place to be and a lot of things to do. Unfortunately it won't be much fun sitting on an Airplane :P
I was looking for a flight ( FS ) to do tomorrow since I want to get one or two in before I go back to school but I think I found one. haha.
Enjoy the heat! I would love to be there now...
Daniel. I hear ya. I feel a southern retreat coming on. It's been kind of tough for Captain Doug the last few months. Time to mellow out on a beach and look at the scenery. :)
Yeah, we only have an hour turn. Enough to tease us. I see it will be sunny and 26C. Nice!
Captain Doug
Thanks, Capt. Doug. Glad you figured it out and mentioned it. I will curb my flying fingers.
My accpreciate the discussion of dispatch interactions and I KNOW that they are talented folks. Without knowing it, you also addressed another pending question dealing with MELs. Glad that you got a replacement airplane in that case. I hope the P.V. turn goes well.
-Craig
Doug & Daniel,
re the "ferry engine" fit, I recall seeing BOAC (Speedbird) and East African Airways Vickers VC10's at Heathrow fitted with an engine ferry pod under the Stbd wing, probably about 8 to 10 feet (3 metres ish) out from the wing root. I may have some pics somewhere but they will take some digging out! Of course, the only remaining operator of the VC10 these days is the RAF; I don't know if they still have the capability. I would doubt it because most (all?) of the fleet is fitted with Air-Air Refuelling (AAR) pods, one under each wing. Also B707, DC8; pics here:
Engine Ferry Pods
Regards / Ian
Hey Doug.... Enter album name here
VIEW SLIDE SHOW DOWNLOAD ALL
This album has 1 photo and will be available on SkyDrive until 4/2/2011.
Hi Craig. Back from PVR. The "turn" went very well. The only glitch was..PVR tower forgot to turn us over to departure frequency so when we checked in they said they were looking for us.
Captain Doug
IanH. Thanks for the great link! Well done.
It even included a shot of Air Canada's L1011. The good ole days. :)
Now here's a technical question....how do you set up a link in the blog's "comment" section?
For example, Engine Ferry Pods. I can do it no problem in the body of my blog but not in the comments section.
Do tell. :)
Is this something to do with HTML tags?
Curious Doug
Getjets. I woud love to include the Powerpoint presentation in my blog.
But "blogger" doesn't like PP. Do you have a link?
I'm not sure what you mean..."view slide show download all." There is no link.
You have to go easy on me, I'm just an Airbus guy. :)
Captain Doug
P.S Who created this presentation. Was it you? :)
Doug,
You're right. You can link sites in the comment section by using HTML tags. You can find out how to use the link tag here!
Edwin. Thanks a million!
Let's see if this works.
Link text
Doug's blog
Edwin. It worked! (Doug's blog)
Proves one thing... You CAN teach an old dog new tricks!!!!
But it does seem a bit of a workout. :)
No problem Doug!
Speaking of old dogs, do you have any L1011 pilots left? If so, have you flown with any? They must have tons of stories from the "good old days".
What happened to the Flight Engineers after you retired the TriStars? Not sure about this, but I think there was a major US airline (Delta perhaps?) that required the FEs to have pilot licenses. But if they didn't have any, would the airlines offer pilot training for them after retirement of the fleet that required FEs?
Is it just me or did my last comment about the HTML tags not show up here?
Edwin
For the folks that posted links and pix related to engine ferrying, Thanks! I guess I had heard of such a thing, but had never seen a picture. It sure makes sense as even 'split' engines are too large for most cargo bays. And- if a replacement engine is needed, the plane remains grounded until the replacement is delivered - not a good thing! I learned a lot today.
Capt. Doug, Your blog is a real winner and I note that you get LOTS of hits. Why is that??? Pretty easy: You post regularly and post interesting details. You respond to virtually every post or question with a reasonable, honest remark. You also have a substantial following of curious folks who follow your lead in keeping it clean, on-topic and generally skirting the tabos. As noted before, being polite in all encounters truly does its rewards. Thanks! I enjoy my time here and I always learn something.
-Craig
Hi Doug,
re the "LINKS", yes it's that HTML thingy but I think you have it. I got the info from Aviatrix, here:
How to Post a Website in a Comment
Pleased you liked the Tristar - The RAF also have a few of those also!! Some are Tanker/Transports and some just plain Transports, i.e., Pax. They seem to be getting a lot of stick recently due to seemingly poor availability/reliability, but they old girls are getting on and spares availability (non-availability) is an issue that the higher "neddies" in the UK MoD/Treasury/Gov'ment do not seem to want to address. And it ain't only the Tristar that is suffering... The Squadron aircrew and maintainers are doing what they can with what they have!!
Apologies - Rant mode off ;)
Kind regards / Ian
IanH. It's time the RAF get some new toys. :) Even the Canadian military recently acquired new toys.
Doug
Craig. You're right about engine size. That B777 engine is huge! Glad to hear you're learned a thing or two. :)
Craig. Between you and I and the whole internet, I'm amazed I don't wake up to lots of "dubious" comments. (I hope I didn't tempt the internet gods) :)
Yes, this is a "G" rated blog. I try to skirt the taboos. I won't talk about security issues nor do I state names. I know many "sources" log in for a visit.
So I make sure I keep things "straight and level." If I do stray, I hope some of my "regulars" will keep me in check.
Craig, thanks for your astute observations. :)
Captain Doug
Edwin. The flight engineers had the chance of getting upgraded to F/O but many washed out. They are all gone now.
I don't think the last comment on the HTML showed up but I read it in my email. :)
Doug
I heard that. [You're welcome!]
Again Dan thanks for visiting enRoute's website! Doug
Craig,
The authors point was that I thought it was odd at the time because I had never seen it before, and wondered if it was normal that a 4 banger would fly with three fans only.........Thanks
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