What to expect? East coast to west coast

[KarenB]

Hi! I posted this on the other board, but I thought I would try it here as well. If you read any of my other posts, I am here because of my fear of flying. If you need more details, here is what I posted the past few days:
http://www.takingflight.us/forums/showthread.php?t=7365

We will be flying from Philadelphia to Salt Lake City, then Salt Lake City to San Diego this Saturday. A few years ago, we flew from Philadelphia to Las Vegas and a few people on this site mentioned that we may hit a few major bumps, drops really, as we neared the Rockys. Yup-we did, but I was prepared and handled it quite well! I was also told about Las Vegas Airport being very near the city.

Is there anything similar I should expect on Saturday? I know the longest part of the flight in on a 757. I can't remember the plane type for the second part as the information is tucked away right now.

Thanks,
Karen

[mkahanek]

Since you are flying into SLC I assume you are on Delta. Your SLC San Diego run will most likely be on a 737. No Airbus as Delta does not fly Airbus. I have flown in to SLC only once. That was in August and I don't particularly remember it being bumpy. Remember seeing the lake. Not exactly attractive in my opinion.

[FromFloirda]

We are flying to Las Vegas from the East Coast on Friday. Can you explain more about the bumps (drops! :eek:) over the Rocky Mountains???

I am so nervous I can hardly concentrate on anything!

[Barb-SAN]

Capt. Hutch must be out flying on a trip right now. He will probably have more to add about how the mountains can cause some "bumps".

I've done the cross-country flights a few times now, crossing the Rockies. Most times there were some bumps there (the mountains affect the flow of air a bit), but it wasn't a big deal. The Capt. turned on the seat belt sign, and kept us seated for 20-30 min. What bumps there were, were not very big. The important thing is that you pay attention to instructions, and stay seated with your seat belt securely fastened. The biggest danger in turbulence comes from walking around when you are supposed to be in your seat...as you could be thrown off balance and fall if there was a big bump. You will be fine in your seat. :thumbsup:

Remember to relax too if it gets a little bumpy...don't grip the seat, or your seatmate, for all they are worth. That just tells your body there is an emergency, and you will get more anxious. If you make your body relax, your mind will follow, and relax as well.

[Captain Hutch]

Dear KarenB and flyer from Florida

I am so glad that you checked in with this website as I see many great suggestions from the other members. So I will try to add a few other tidbits that might help. I have not looked at the physics of flying websites so I will assume from the other comments that this has some good instruction on how an airplane actually flies. I have a degree in physics (and electrical engineering if it matters—no, I won’t tell you that electrons hold up the wings!) if it helps. I will try to use the comparison to a boat in a stream to compare to an airplane in the air. The boat is moving along on a mass of water like the airplane is moving through a mass of air. If the boat is trying to cross from one side of the stream to the other and is moving perpendicular to the flow of water, the boat will have to compensate for the movement of water to reach a point directly opposite from where he left. Naturally, if the boat wants to go downstream, it will have the added speed of the water to help it along, or upstream the boat will of course be slowed down. Likewise the aircraft, if it is moving the same direction as the air mass, will be helped along by the air mass and make it to its destination quicker—a tailwind! For the most part, this huge air mass that surrounds the earth has some sort of movement associated with it, and then some variations with it that change with altitude. The jet stream is like a huge tube of moving air that flows along kind of ignoring the movement of the air mass that it moves through. If an aircraft flies through this boundary of where these two air masses are located, there will be turbulence just as you see when two steams come together. An aircraft is almost guaranteed to experience turbulence under these conditions, and if you really want to see your chances of getting some bumps, check for the forecast altitude and location of the jet stream compared to your route of flight.

Back to the stream of flowing water. If there are a lot of rocks on the streambed over which the water flows, you probably will see ripples on the surface of the water if the water is flowing fairly rapidly. Similarly, if the air mass is flowing fairly rapidly over the mountains, the effect will be felt at a fairly high altitude, maybe even with a few drops or rises as you have noted. I have flown over the Appalachian Mountains a fair bit, and even though the air is quite smooth up until we get to the mountains, in most cases we will experience light turbulence, though not much more when actually flying over them. I have not flown over the Rockies in quite a while, but I would just always expect to experience turbulence here too. Usually the dispatchers, the guys who actually plan the routes for the pilots, will plan for the smoothest flight possible. Go ahead and ask the pilots if they expect any turbulence over the mountains, maybe they will have a little more information. Remember, the aircraft is flying in a huge mass of air molecules (along with a few other types of molecules of course), otherwise it wouldn’t be flying. If there was a vacuum, you would be in a rocket ship.

Now, on a personal note, I have great confidence in the ability of airplanes to fly, perhaps because of my early days in aviation by flying my body alone through the air or testing a military plane to its max. I am an extremely conservative airline pilot—I am solely interested in providing a safe and smooth flight for all of those passengers who entrust themselves to all of us crewmembers for that short period of time. But when I flew the A-10, on a few occasions I would take it up to a high altitude, usually above 20,000 feet, with nose directly in the vertical until it ran out of airspeed—zero!—and then let the nose fall earthward, the aircraft would pick up speed and fly by itself. Perhaps I wasn’t worried because I was wearing a parachute and sitting in an ejection seat! (Okay, that is the story that you wanted to hear!) And you may be surprised to hear that an airliner can glide with no power at all. With both engines failed on the 737 the glide ratio is about 12:1, meaning that for every mile high the aircraft is over the ground it will glide 12 miles in the horizontal (corrected for winds of course). By the way, in aviation we normally talk about nautical miles (a nautical mile is about 6080 feet—slightly different for the Brits—KARI!:lol: ) instead of the 5,280’ statute mile, and knots for airspeed, or nautical miles per hour. Years ago when the Boeing 767 came out, there was a mix-up in the fuel load, pounds vs. kilograms (fuel measured in weight) and the aircraft ran out of gas during cruise altitude. The pilot was an experienced glider pilot and actually dead-sticked—flew/glided with absolutely no power—the aircraft to a safe landing—to an airport in Canada I think. Talk about appreciative passengers!

Well, I hope you were able to wade through all this and that I actually answered your question. Have a good flight. :tiphat:

Hutch

[Barb-SAN]

Back to the stream of flowing water. If there are a lot of rocks on the streambed over which the water flows, you probably will see ripples on the surface of the water if the water is flowing fairly rapidly. Similarly, if the air mass is flowing fairly rapidly over the mountains, the effect will be felt at a fairly high altitude, maybe even with a few drops or rises as you have noted....

Well, I hope you were able to wade through all this and that I actually answered your question. Have a good flight. :tiphat:

Hutch

Enjoyed your long answer...I can easily visualize the rocks in the stream and how you will see ripples on the surface. It makes sense that the mountains could disturb the airflow in a similar pattern.

[KarenB]

Thanks Captain Hutch!

[Captain Hutch]

:wave: You are welcome, KarenB! I would be interested to hear how your flight into Salt Lake City went.

Hutch

[Jeff California]

Thanks Capt. Hutch. I enjoyed reading that.:)

[Captain Hutch]

Ye're welcome, Jeff. Glad you enjoyed reading it as much as I enjoyed writing it! :)

Hutch

[KarenB]

:wave: You are welcome, KarenB! I would be interested to hear how your flight into Salt Lake City went.

Hutch

It went very well! I posted a "we are back!" thread on the other board.