I just got back from a trip to Bali, Indonesia. While I was on my way there, the People’s Alliance for Democracy, or PAD, stormed Suvarnabhumi International Airport (BKK), in Bangkok, Thailand. The rebels want to force change in Thailand and they feel that shutting down the airport can help their cause. This is somewhat scary because I was just in BKK a few nights ago and have friends doing their 747 training who are flying there right now. I don’t have a way to get a hold of them, but Cathay does a pretty good job of avoiding trouble. Many flights have diverted away from BKK, so hopefully, there is no trouble. Undoubtedly though, there are Cathay crews that are overnighting there right now, so I hope all is well with them.

By the way, if you are an American, I must say that you accidentally mispronounced Suvarnabhumi Airport. It’s pronounced “su-waan-na-poom” because the transliteration from Sanskrit to English doesn’t accurately portray how the word should be pronounced. Now you can sleep tonight!

Going back to Bali was amazing for me. Growing up in Yogyakarta, (pronounced “jo-ja-karta”) just a little West of Bali, it was great to visit the amazing beaches there. Bali is a resort for Western tourists because it has a great tropical climate and white, sandy beaches.

As we approached Bali, we passed a dormant volcano just off our right, that extends upwards of 11,000 feet. At 14,000 feet as we passed by, the peak looked pretty close, and I was able to snap a photo, the one you see at the top. Click that photo to see a few more photos that I took during my short time there. I was lucky enough to get a smooth landing into Bali and pull up to the gate where I had last been as a child. As we taxied into the gate, we could see the ocean waves washing up on the beach, just off the runway, and oh, how I wanted to stay!

The last time we were there was 1983-ish and I was only 5 years old. Back then, it was my dream to fly 747’s and it was so neat for me to be able to go full circle and pull up to the gate as a 747 pilot for Cathay. It just goes to show that anything is possible with God’s grace. If you have a dream, follow it with all you’ve got, and it very well may come true. I get pretty sentimental, so when I did the walk around, I took my camera and relished each step I took, thinking that the last time I walked here, I was 5 and living in Indonesia.

The air was clear and cool and I desperately wanted to stay longer than the hour we had on the ground there. I got a few snaps of the airplane, and then with me (Phatty McButter Pants) in front of it, to give some perspective on size — no, not of me, but of the 747. :o)

As I took my last step off the tarmac and onto the jetway steps, I lingered for just a second. I didn’t know when I would be back to Bali, and wanted to savor the moment. It was not unlike the scene in the movie “We Were Soldiers”, where Mel Gibson is one of the first American soldiers to step foot onto Vietnamese soil. He makes note of that moment, wondering what the future will hold for him and his U.S. troops there. My moment wasn’t so serious, but I was just glad to be there.

The high terrain around the airport climbs to around 10,000 feet, not including the volcano. What looks pretty for tourists is actually a real concern for us pilots. In good weather, avoiding the “terra firma” is no big deal, but with fog, clouds, and air traffic controllers without the latest technology when it comes to radar and training, makes the situation a little more serious. In those cases, the onus is on ourselves to keep everyone behind us in their seats eating meals and drinking wine, safe and sound.

On the taxi out, heading back to Hong Kong, we saw an MD-80 off-loading it’s passengers, a regional flight from somewhere. Stairs were wheeled up to the front door of the plane, while passengers also disembarked out the rear of the plane. The rear entrance always brings back memories for me because it was always so scary for me as a kid. The APU, or auxiliary power unit, sits back there and is a small jet engine itself, that powers the plane with electricity and air conditioning while the engines are shut down. It’s loud, and sits in the tail section of the plane. Because the engines are also in the rear (see the pictured link) small kids like myself think the big scary engines are running and are going to get them. I loved planes as a kid, but cried every time we embarked via the rear steps of the DC-9’s and MD-80’s. So as we taxied past, memories from Indonesia as a kid flooded back to me. I had to focus on the job at hand, but it was great fun to be back.

At some point, I’d love to get my family back over to Bali and Yogya, so we can remember old times. For now, I’m left with the sweet memories that I made when visiting my old stomping grounds, this time, on the other side of the cockpit door as a pilot. It was just an hour, but it was a great time in Bali.

TobyLaura.com

The longest flight that Cathay Pacific flies is between New York (JFK) and Hong Kong (Chek Lap Kok). To be nit picky, flying to JFK is longer in mileage and flying back to Hong Kong is longer in flight time. Why is this? The answer lies in the understanding of great circle routes and jet stream winds.

Winds generally flow from West to East, so a flight leaving New York and headed for Hong Kong would be facing a headwind, whereas a flight leaving Hong Kong and flying to New York would have the wind at its back, helping push it along. Therefore, the flights into strong headwinds want to fly a route that covers the least amount of mileage across the ground because flying into headwinds slow planes down and costs money in extra fuel costs. When flights have a good tailwind helping push them along, an extra few miles added to the distance is negated by the help of the wind.

The next factor, beyond winds, is how to actually fly a route that takes the least amount of ground miles to go from point A to B, in this case, JFK and HKG. A great circle is a plot along the surface of a sphere that represents the shortest distance between those two points. Point A and B lie on a circle that cuts the Earth into two exact halves and represents the largest circle that could be drawn from the shape of a sphere – the Earth. The Equator is a great circle, cutting the sphere into equal halves and is the largest circle that can be derived from the spherical shape of the Earth. All other lines of latitude (think of rungs on a ladder) are not great circles, because lines of latitude don’t cut the Earth in half as they move toward the poles. However, lines of longitude (think of the long way down) are great circles, because they each can cut the Earth in half and go through the center of the Earth.

Now to twist the brain a little farther, imagine our two points on the Earth as being HKG and JFK. Any two points on a sphere (and even though the Earth is not a sphere, that goes beyond the scope of our discussion — read about a Geoid for more info) can be put on a great circle that cuts the Earth in half, or cuts through the center of the Earth. It might look something like this:

Using this method, we arrive at the path that is the shortest distance between two points on a sphere. If NYC and HKG are two points on a circle that cuts the sphere in to two equal halves, then that circle runs up near the North pole. Here is another view of JFK-HKG, looking at the Earth from above the North Pole:

You can see clearly that the “circle” this path creates, cuts right through the center of the Earth.

The airplane won’t fly this exact route due to weather, airspace air traffic control restrictions. Also, the flight has to remain within a certain safe distance of a suitable landing airport, incase of trouble. But, on the whole, this is about where the plane will fly. Because this is the shortest route possible, it seems strange to be heading almost due north out of New York to head for Hong Kong!

We get so used to the Mercator projection, where the map of the world is formed to wrap around a cylinder (instead of one that would wrap around a sphere) so that straight lines on those maps represent lines of a constant course.

The trouble is that it the farther from the equator one looks, the more “distortion” there is. No — Antarctica is not the same size as Russia and Greenland is not the same size as Africa! It’s not really a distortion, but the size of a landmass has to change so the goal of the map (all straight lines represent a constant course) remains true. When a great circle route is drawn on a map with Mercator projection, we get those familiar curving paths that are seen in the backs of airline magazines. The curve is accurate for the map, but the airplane is not constantly turning, like the map line would suggest. We are so used to viewing of the world through Mercator projection, that when we think of taking a flight from JFK to HKG, we would be passing overhead the Colorado rockies, then the Golden gate bridge, then the sunny beaches of Hawaii and the Philippines, and then descend into HKG.

However, this couldn’t be farther from the truth, because that would be so much father, and take so much longer than flying a great circle route. The Mercator map is lying to you! Put a string over a globe and see how much farther flying the “mercator method” is versus flying the great circle route. The shortest way across the globe from NYC to HKG would be close to crossing the north pole and then next map projection will show that to be true.

Another map projection is the Gnomonic projection, where all straight lines on it represent great circle routes. That might help a pilot get a general idea of what countries he will cross when flying a great circle route, but for the most part, isn’t much help because of it’s extreme distortion from the actual size and view of the continents. As you can see, it also isn’t much help to school kids to learn their countries.  It is similar to the Google Earth view from overtop the North pole. 

Flights that travel Easterly, like our example from Hong Kong to New York, don’t always travel the great circle route. This is because of the high tailwinds that can be achieved by following closer to the route of the Jet Stream. Even though deviating from the great circle route adds track miles to the route, the winds pushing the flight along more than make up the difference of flying a farther distance. In this case, the route of flight would head well south of North Pole. The flight would head out over Japan, over the North Pacific, and then make landfall around Anchorage or Vancouver, and then over the northern U.S. or Southern Canada, and then into NYC. A lot more miles, yes, but much faster and less fuel is burned, thanks to winds of up to 200 miles per hour, pushing the flight along.

The great circle route, though a simple concept, is much harder to explain than it is to understand. The flying of these routes has opened up a whole new era in air travel. Because airliners have navigational computers that can calculate these routes, greater and greater distances can be flown, connecting more and more cities. The next time you are headed overseas to a tropical paradise, especially over the Pacific, look out your window and look down. If you see ice and snow covered plains, you’ll understand why and have it make sense to you. It’s all about traveling the shortest distance and forgetting about the world as a flat map on the wall.

Just as an aside note, the four longest scheduled flights in the world are:

1) Singapore – New York (Newark) 9,500 miles (Singapore Airlines)
2) Singapore – Los Angeles 8,700 miles (Singapore Airlines)
3) Bangkok – New York 8,600 miles (Thai Airways)
4) Hong Kong – New York 8,100 miles (Cathay Pacific)

The flight times and distances are staggering and hard to comprehend. Remember, these are non-stop flights. Over three hours flight time separate flight number one from flight number four, and only the ultra long range Airbus A340-500 and Boeing 777-200LR can make the Singapore – New York run. Singapore to New York is over 18 hours flight time, so if one of these above flights are in your future, may I recommend that you save up enough money for business class? If not, at least bring some binoculars to look for Santa on your way “over the top.”

TobyLaura.com