Airport traffic

In his book, "Cockpit Confidential," airline pilot and commercial aviation blogger Patrick Smith devotes a chapter to airport traffic and the source and likely solutions to delays.

The book's available here: http://www.askthepilot.com/cockpitconfidential/ I highly recommend it.

He first details the wrong solutions and argues against them. Notably he says some things against satellite airports, which reminded me of many things I've said about Toluca. Later he proposes his own solution, which boils down to reducing the number of flights by using bigger airplanes.

This is something we've discussed here as well. The effects on traffic are undeniable. Fewer flights means fewer traffic. This would mean turning to mid-size and wide-body airplanes. And I'm just not sure how practical this would be for the airlines.

Take a case I know something about, the MEX-MTY route (that's Mexico City to Monterrey). Typically you have three airlines, Aeromexico, Interjet and Volaris, offering hourly flights each starting at 6:00 am and until around noon, with those airplanes returning to Mexico City. For Interjet this is 7 A-320 flights (not necessarily 7 aircraft, take note), each carrying 150 passengers (all their A-320s carry exactly that number, in a 3-3, 25 rows configuration), for a total of 1,050 passengers (likely, though, perhaps 950-1,000 people actually fly).

Never mind Interjet's fleet is made up of A-320 and a few smaller regional-type SU100 Superjets, or that they own an A-320 maintenance facility. Let's assume they can change their fleet. In order to offer only 3 flights for the same number of passengers, they'd need 3 aircraft capable of siting 350 people each. I think that's 747 territory. For 4 flights, they can make do with room for 262 passengers each, which does fit planes like the 767.

Assuming similar numbers for the other two airlines (and I know they pack their jets tighter), this would remove 6 flights in a 6-hour period, leaving 3 flights operating at nearly the same schedules (6, 8, 10 and noon). But this helps because a delay in any one flight would have a 2 hour buffer, let's assume, for the next round of flights.

The problem is much more complicated than that, of course, as there is traffic to and from other destinations at both ends, notably to Guadalajara, Cancun and Houston. But the solution would help.

For a few years.

I mean, if more people want to fly and are able, then the demand will outstrip the supply, and years later you'll have the same problem only with bigger airplanes.

And the problem really isn't that bad at MEX until delays pile up later in the day. Mr. Smith says the on-time rate in the US is 85%. I'm sure in Mexico it's higher than that, very likely because we have fewer lights in proportion to the population.

On other things, I had a question and a thought.

The question is, does the info from the Flight Data Recorder (aka "black box") ever gets used for anything other than accident investigations? Since modern ones record a great deal of performance data from all kinds of instruments, wouldn't it be useful for maintenance? or to measure the durability of parts and systems? No question of removing the FDR from the plane, but there could be a backup or duplicate in the avionics bay which ground crews could access.

Now the thought. The FDR and CVR (Cockpit Voice Recorder) are used in accident investigations. Indeed that's the whole reason they exist in the first place. They're designed to withstand shock and fire, and are placed in areas of the plane where they'll most likely survive. even so, sometimes they go missing, especially in ocean crashes, and sometimes the whole aircraft goes missing, as just happened with MH 370.

Suppose planes could transmit the same data going into the "black boxes" to interested parties nearby, just in case the plane or the boxes go missing.

That's a tall order. With millions of flights every week, the data bandwidth used up would be vast. And 99.999999999999999% of all that data would be useless. Why bother keeping an external record of a normal flight between Podunk and Chicago? Or London to Dubai? So we'd need to trim this down to manageable levels. not only that, but to make it take place only rarely. Too many false alarms activate the "cry wolf" syndrome.

We'd need some system in place, say if, above 10,000 feet, altitude were to change by more than 2,500 feet or course were to change by more than a few degrees, then the FDR and CVR would start transmitting data via satellite or radio, or both.

Of course, in the event of, say, loss of power to all engines, it would be smart for this system to be turned off. it would also need to recognize a planned descent, otherwise every plane coming in for a landing would trigger the "cry wolf" response. And those are just two problems I can see. Surely there are many others.

But imagine how different things would be for those who've lost friends and family in the MH 370 tragedy, of the Air France accident over the Atlantic some years ago. With something like this in place, we'd know better where to look for the wreckage, and would have at least some notion of what happened.

I know this would be useful only in extremely rare cases. But consider all planes carry life jackets and emergency oxygen masks, which are rarely used even in most accidents.

Quote: Nareed

. Later he proposes his own solution, which boils down to reducing the number of flights by using bigger airplanes.

This is something we've discussed here as well. The effects on traffic are undeniable. Fewer flights means fewer traffic. This would mean turning to mid-size and wide-body airplanes. And I'm just not sure how practical this would be for the airlines.

The switch from narrow body to wide body airplanes for short haul routes is an extreme case and really is unlikely to affect any routes in Northern or Latin America. Mexico has no routes with over 50 planes per day, and probably only MEX-CUN with over 30 flights per day.

Quote: COMPARING THE ENVIRONMENTAL IMPACT FROM USING LARGE AND SMALL PASSENGER AIRCRAFT ON SHORT HAUL ROUTES

In the summer of 2006 airlines operating between the London airports and Amsterdam Schiphol (371 km great circle distance) have been offering 55 daily oneway services, using aircraft with an average seating capacity of 125. Between Heathrow and Schiphol alone, there were 26 daily one-way services, and these were offered by an aircraft fleet with an average capacity of 143 seats.

If airlines have utilised a fleet of wide-body aircraft instead of narrow-body aircraft a much lower frequency of service would have been required to offer similar seating capacity. This could have freed scarce runway and air space capacities and could have reduced congestion at these airports.

At the other side of the world, Japanese airlines operating between Tokyo and Sapporo, also a short haul route in airlines’ terms (820 km great circle distance), offered 51 daily one-way services but utilising a fleet of aircraft with an average capacity of 395 seats. Most of these services were provided by a high seating capacity version of the Boeing 747.

Generally what the writer is talking about is the decision to use large fleets of very small planes in the USA. For instance the 50 planes mostly under 40 seats that fly between San Diego and LAX (129 miles). Very small planes need triple the spacing between planes which magnifies their impact on the runway.

In any competitive environment the airlines will try to downsize their jets, Customers value frequency, and they want to provide that.

Mexico really only has three transfer airports (MEX, GDL, MTY). They may have to prohibit turboprop flights at Mexico City, and if they charge fees per landing and takeoff instead of per weight, the airlines will fly their A321's instead of A320's out of MEX.

Quote: Pacomartin

The switch from narrow body to wide body airplanes for short haul routes is an extreme case and really is unlikely to affect any routes in Northern or Latin America. Mexico has no routes with over 50 planes per day, and probably only MEX-CUN with over 30 flights per day.

30 per day, really? That seems like a lot.

The point is:

Quote:

In any competitive environment the airlines will try to downsize their jets, Customers value frequency, and they want to provide that.

Exactly. I don't fly much for business, but I appreciate having several options when I do. You should see the sour faces when I'm asked to look up flights to places like San Luis Potosi or Durango, for which the airlines offer few choices. Often they have to leave the day before, or return the day after their appointments.

Smith does mention this, and says passengers need to change their habits. The airlines won't be able to make them, and any regulation dictating a minimum plane load would meet an awful lot of resistance.

Quote:

Mexico really only has three transfer airports (MEX, GDL, MTY). They may have to prohibit turboprop flights at Mexico City, and if they charge fees per landing and takeoff instead of per weight, the airlines will fly their A321's instead of A320's out of MEX.

I'm not sure about Viva. Volaris does own some A321s. Interjet is all A320 plus now the SU100. Aeromexico is joined at hip with Boeing, and I've no idea what varieties of 737s they operate. Bottom line, there aren't that many a321s, nor is the difference in capacity that big to begin with.

The thing is most flights within Mexico are 60 to 90 minutes long. the exceptions being MEX/MTY-Tijuana/Cabo. At that there are shorter flights, like MEX-Acapulco or MEX-Bajio. Wide bodies for such small distances are frankly ridiculous, unless you have a Japanese-type population density and affluence.

BTW, I'm told at some time Aeromexico operated a flight MEX-Puebla. That's a very short distance, less than 150 km, or so. I hardly think even a regional jet could get up to cruising altitude.

Later, Alma, a short-lived low cost, offered a Toluca to Puebla flight. That made a bit more sense, at say around 220 km. But still rather a short flight. It made more sense if you consider you have to either drive through Mexico City, which can add as much as 90 minutes, or take a long detour which would add at least 60 minutes.

Quote: Nareed

30 per day, really? That seems like a lot.

I remember looking it up. It was very high, almost as high as LAX to SFO. But of course LAX-SFO is only the most popular route from Los Angeles area to San Francisco.


An annual figure of 3.5 million is about 10,000 people per day. If you carry them 100 at a time that is 50 flights each direction. If you carry them 200 at a time that is 25 flights each direction. Somewhere in between is over 30 flights per day in each direction.

Quote: Nareed

Exactly. I don't fly much for business, but I appreciate having several options when I do. You should see the sour faces when I'm asked to look up flights to places like San Luis Potosi or Durango, for which the airlines offer few choices. Often they have to leave the day before, or return the day after their appointments.
The thing is most flights within Mexico are 60 to 90 minutes long. the exceptions being MEX/MTY-Tijuana/Cabo. At that there are shorter flights, like MEX-Acapulco or MEX-Bajio. Wide bodies for such small distances are frankly ridiculous, unless you have a Japanese-type population density and affluence.

With 15 wide bodies in the entire country, the only route is Aeromexico uses them to fly from Mexico City to Cancun. Even that flight is rare, and is probably done to give the plane something to do for a few hours in between long hauls.

But JFK-LAX (2470 miles) is flown by a ridiculous number of planes. Frankly if you end up with a very busy route the airlines are more interested in catering to the money who want choices and plush options. American flies Airbus A321 with only 102 seats instead of normal configuration of 181-187 seats. Jet Blue flies an Airbus A321 with 159 seats for that route instead of normal configuration of 190 seats.

Here are a few routes Emirates flies with the Airbus 380 (under 3000 miles)
310 (EK) Dubai (DXB) – Bahrain (BAH)
530 (EK) Dubai (DXB) – Kuwait (KWI)
1,060 (EK) Dubai (DXB) – Jeddah (JED)
1,200 (EK) Dubai (DXB) – Mumbai (BOM)
2,700 (EK) Dubai (DXB) – Rome (FCO)
2,770 (EK) Dubai (DXB) – Prague (PRG)
2,830 (EK) Dubai (DXB) – Munich (MUC)
2,928 (EK) Dubai (DXB) – Milan (MXP)
2,960 (EK) Dubai (DXB) – Zurich (ZRH)

========================

A319/A320/A321 are certified for 156/180/220 passengers
Only Viva packs A320 with all 180 seats, Volaris puts in 174 and Interjet only 150

The new versions from Airbus will be certified for more. Volaris and Interjet have 50 firm order apiece. Viva has 40 firm orders.
A319neo/A320neo/A321neo are certified for 160/195/240 passengers

Only Aeromexico flies over 20 planes with only 124 seats, but they will be retired in two years.

But I am sure that Aeromar takes up an inordinate share of runway time at MEX. The authorities must be pulling their hair out to decide if they should force Aeromar out of business before the new airport gets built,

Statistics are for 2014
1 MEXICO CANCUN 3,524,000
2 MEXICO MONTERREY 2,736,000
3 MEXICO GUADALAJARA 2,379,000
4 MEXICO TIJUANA 1,266,000
5 MEXICO MERIDA 1,131,000
6 TIJUANA GUADALAJARA 1,025,000

1 MEXICO LOS ANGELES 813,000
2 NEW YORK CANCUN 803,000
3 LOS ANGELES GUADALAJARA 781,000
4 NEW YORK MEXICO 760,000

The Mexico-Cancun route rivals the busiest in USA, where the statistics are for all the airports in the metro area. I am sure MEX-CUN is larger than any single airport pair in the USA
June 2014 - May 2015
1 Chicago, IL (Metro Area) New York City, NY (Metro Area) 3,950,000
2 Los Angeles, CA (Metro Area) San Francisco, CA (Metro Area) 3,640,000
3 Los Angeles, CA (Metro Area) New York City, NY (Metro Area) 3,370,000

ORD-JFK 737 miles / 1190 km
MEX-CUN 799 miles / 1290 km

Quote: Pacomartin

But of course LAX-SFO is only the most popular route from Los Angeles area to San Francisco.

Was that on purpose? :)

Quote:

With 15 wide bodies in the entire country, the only route is Aeromexico uses them to fly from Mexico City to Cancun. Even that flight is rare, and is probably done to give the plane something to do for a few hours in between long hauls.

One thing often left out when talking of the demise of Mexicana, is that now there is only one airline with wide bodies or long haul flights. Interjet's longest flight is MEX-JFK (they actually serve one sandwich in addition to snacks in that route), and the second must be MEX-Bogota. Among the low-costs, the largest plane is the A-321.

Mexicana used to fly to London and Brazil in 767s. Much earlier, like late 80s, they flew DC-10s MEX-ORD via MTY. Back then they had a code share with BA for flights ORD-London.

I suppose it's not out of the realm of possibility that one of the low costs would go into the intercontinental business eventually. There is some market for it. In addition to Aeromexico, there are daily flights by AF, Iberia, Lufthansa and KLM. But long haul intercontinental service in wide bodies goes against the current model. For one thing, they'd have to serve meals in flight. This may seem trivial, but there's appreciable weight and expense involved. There's a reason many airlines have done way with in-flight meals. Remember when any flight over 60 minutes merited one hot meal?

Quote:

But JFK-LAX (2470 miles) is flown by a ridiculous number of planes. Frankly if you end up with a very busy route the airlines are more interested in catering to the money who want choices and plush options. American flies Airbus A321 with only 102 seats instead of normal configuration of 181-187 seats. Jet Blue flies an Airbus A321 with 159 seats for that route instead of normal configuration of 190 seats.

I grew up at a time when any trip 5 hours or longer required a wide body, with room to move around and at least one movie shown on overhead screens. In a way it still does. that's a long time to remain seated. But you won't be able to offer several flights a day in huge jets. So you make room in smaller ones. I don't think we're close to an all-business A-320/B-737 with a bar or lounge at the rear, but it's bound to happen with current trends (ie, more frequencies and longer ranges for smaller planes)

Quote:

Only Viva packs A320 with all 180 seats, Volaris puts in 174 and Interjet only 150

I describe Interjet as a passenger airline, rather than a livestock one. There is a reason for that.

Quote:

But I am sure that Aeromar takes up an inordinate share of runway time at MEX. The authorities must be pulling their hair out to decide if they should force Aeromar out of business before the new airport gets built,

Completely useless. if you force it out of business, all its flights will be replaced by Interjet SU100s and Aeromexico's Embraers. Interjet is already competing in the MEX-SLP route.

Quote: Nareed

Was that on purpose? :)

Yes. Los Angeles Metro area has several airports, LAX, Burbank, Long Beach, Ontario, and John Wayne. San Francisco metro area has SFO, Ontario, and San Jose. So when you give the number of passengers between metro areas it could involve any two airports. But of those combinations, obviously most passengers fly LAX-SFO.

The country of Mexico has no competing or relieving airports with the exception of Toluca and MEX compete somewhat for Mexico City passengers. So flights from Mexico City to Cancun necessarily mean just the two airports. I think MEX-CUN carries more passengers than any airport pair in the USA, but not as many as metro NYC to metro Chicago. Metro NYC means Newark, LaGuardia, and JFK flying to Ohare and Midway in Chicago.

MEX is still smaller than London Gatwick (the busiest single runway airport in the world). MEX has two runways, but as we discussed earlier they are so close that one is used for landings and the other for takeoffs exclusively. I don't think Gatwick has forbidden turbo props or regional jets, but they get very few. On the other hand, unlike Mexico City there are five airports to choose from. Regional jets are more likely to take off from London City airport.;

2014
38,105,747 London Gatwick Airport Increase 7.5%
34,255,739 Benito Juárez International Airport Increase 8.6%
18,756,997 San Diego Airport (busiest single runway airport in the USA) |Private jets permitted and even encouraged

I think that MEX won't make it until the new airport is built without prohibiting turboprops and regional jets from flying there.

Quote: Pacomartin

The country of Mexico has no competing or relieving airports with the exception of Toluca and MEX compete somewhat for Mexico City passengers.

Not anymore. Maybe if the new airport is delayed, Interjet and Volaris get aggressive expansion ideas, and someone does something about transportation costs to Toluca. Otherwise I'm afraid Toluca is done for. Perhaps also if someone comes up with a luxury airline using executive jets. I mean with regular service rather than on-demand or charter services.

Quote:

I think that MEX won't make it until the new airport is built without prohibiting turboprops and regional jets from flying there.

Again, not possible. Aeromexico, the 800 lb gorilla, and Interjet both use regional jets. Add their total market shares and tell me if the new airport won't accommodate them. Maybe in 20 years, but not now. besides, the old airport will close. So where would flights to Zacatecas, SLP, Oaxaca and such low-demand destinations leave from? Toluca? No doubt the Mexico State government would love it, but there's still the transportation issue.