Please turn off all personal electronic devices

[Timepass]

You don't seem to be getting that I'm not talking about speed at all--I fully understand the difference, and I'm telling you it doesn't matter. I'm talking about engine-internal performance and airworthiness. Are you really trying to say that wind has nothing to do with the handling characteristics of an aircraft?

No you are wrong. All that matters to an airplane is Airspeed. All the systems on it only matter on airspeed.

Yeah inconsitend airspeed is hard on planes parts but that goes the same for headwinds and tailwinds.

Like IR said they like landing and taking off into headwinds because it means that there ground speed is lower for landing and take off but there airspeed is the same.

Speed is all relative to what you are messuring it from. For the parts on a plane all that matters is how fast is the plane moving relative to the air around it. Plus you IJ is a pilot. I dont think you are going to win a fight with some one who has real world experince in this.

 

[sushi]

You still don't seem to be getting the difference between ground speed and airspeed. Airspeed is not affected by wind direction and speed. Not, as in, not. The flight controls are not affected either. Not, as in, not.

Well put IJ.

It does seem that some still do not understand the difference between airspeed and groundspeed after previous discussions.

Too bad we can't take these folks out for a demo so they can see the difference in the real world.

Plus you IJ is a pilot.

As are some other folks in this discussion.

 

[matticus008]

No you are wrong. All that matters to an airplane is Airspeed. All the systems on it only matter on airspeed.

Yeah inconsitend airspeed is hard on planes parts but that goes the same for headwinds and tailwinds.

Like IR said they like landing and taking off into headwinds because it means that there ground speed is lower for landing and take off but there airspeed is the same.

Speed is all relative to what you are messuring it from. For the parts on a plane all that matters is how fast is the plane moving relative to the air around it. Plus you IJ is a pilot. I dont think you are going to win a fight with some one who has real world experince in this.

I'm not fighting with him. Honestly, I don't even think we're talking about the same thing, since he seems to be on about airspeed and groundspeed. Airspeed is certainly not the only concern to an aircraft, and certainly not to its engines or its stability in choppy air. Air (or ground) speed is only one factor in the handling of an aircraft, and the engine operates on specific principles of physics.

Turbofan engines operate economically with constant power application--not variable spin up and down in response to a tail wind. If a pilot maintains constant power to a turbofan, the tailwind can boost the ground speed and shave time off the flight. If the pilot spins down the engines every time there's a "boost" from the wind (which is the original point I responded to and not posted by IJReilly), it's not necessarily going to save fuel. Moving into light head winds is not always a bad idea on heavy, turbofan-equipped commercial craft, again takeoff and landing being two such situations (the choice extends beyond speed considerations--pilots seek to avoid cross winds on the runway and laminar flow is most stable in a head wind), along with harsh oncoming fronts as well as other atmospheric conditions civil pilots do not face. Even on piston-powered personal craft, it's still not terrible or undesirable to turn into head winds sometimes. In the right situation where a pilot can take advantage of a tail wind, they do, but flying in head winds is more common, as IJReilly pointed out...but it's not because there is more wind going in the opposite direction of a given plane on a given flight or because air routes mostly happen to be against the wind.

There are many pilots in this thread, and IJ is not the only one. I'm sure there are also non-pilot aviation industry people here, too.

 

[skoker]

WHAT??

Gate servicing also creates far bigger delays than runway backups--planes can take off at a rate of one per minute or so if there is a clear exit vector, but gate servicing takes a solid 25-30 minutes even at perfect efficiency. There's also fewer gates than empty tarmac for planes, which has a funnel effect meaning that gates are the most precious resource on the ground and no plane that doesn't need to be at the gate is allowed to stay. If arriving planes don't have gates, flight crews can't switch planes and there's a snowball effect on the delay.

First off, unless you're flying a 'legacy' carrier, that's not true at all. At SWA, they shoot for a 25 minute turn (and this is from pull-in to push-back), and i've seen it happen.

Classic Example:
Last year, waiting for my flight MCO-BUF, ops agent came and told us that we would be delayed due to the aircraft arriving late due to fog in Manchester. Flight scheduled for 11:15, acft arrived at 11:06 from Manchester, and everybody was off, plane cleaned (very well I might add), and we reloaded and pushed at 11:18. THAT'S FAST!!!

Second of all, flight crews nowadays often keep the same aircraft for an entire shift. This isn't true for all carriers.

 

[Timepass]

WHAT??



First off, unless you're flying a 'legacy' carrier, that's not true at all. At SWA, they shoot for a 25 minute turn (and this is from pull-in to push-back), and i've seen it happen.

Classic Example:
Last year, waiting for my flight MCO-BUF, ops agent came and told us that we would be delayed due to the aircraft arriving late due to fog in Manchester. Flight scheduled for 11:15, acft arrived at 11:06 from Manchester, and everybody was off, plane cleaned (very well I might add), and we reloaded and pushed at 11:18. THAT'S FAST!!!

Second of all, flight crews nowadays often keep the same aircraft for an entire shift. This isn't true for all carriers.

That still does not change the fact that Gate servicing is still the biggest bottle neck at an air point. It takes the longest to do and have the least ammount of space to handle it.

Yeah in gate Servicing a plane can make up a lot of time by them speeding tha up but still a Plane being late leaving a gate means another plane risk getting behind. I thinking they set up gate time to be 25-30 mins. But still look at the lag time between a plane pushing off from a gate to the next plane pulling up. There just is not much time bettween them. Also gate deleys are one of the few delays that are easy to control and limit. A gate deley should be the last place for a delay to happen.

Yeah if the gate is not needed the plane will sit at the gate. But if the gates need for another plane yeah the orginal plane is going to push off and open it up.

In lovefeild (Dallas) storms over houston caused my plane to be deleyed taking off because Houston Air space was over crowded and not like we could of land when we got there so they where delaying any flight that had to into houston Air space. We just sat at the gate but then again I was on of the later flights of the day so there where other free gates to send a plane 2 and the deley in houston also reduced the cruch on lovefield (where a lot of it traffic does come from houston).

Basicly if the gate not needed for another plane they will stay there for a deley. But if it is needed for another plane they will push off

 

[aquajet]

Not, as in, not. The flight controls are not affected either. Not, as in, not.

Huh? I'm not certain that was clear enough.

 

[IJ Reilly]

Are you really trying to say that wind has nothing to do with the handling characteristics of an aircraft?

Correct. In terms of flight, wind as we normally think of it, only matters in relationship to the ground. Not to get too technical, but "relative wind" is the wind that matters to flight. It's the one that flows over airfoils and control surfaces, and allows airplanes to fly.

http://avstop.com/AC/FlightTraingHandbook/RelativeWind.html

With that, enough explanation -- I'm out.

 

[Silentwave]

BUSTED!

They pretty much found that modern aircraft are so heavily shielded that even cell phones have little effect. However when they were testing phones with just the equipment on it's own, the equipment got confused.

OK I've read this part a few times in this thread but keep getting this nagging feeling. I seem to remember that the airliner in question was a private jet of the LATEST and Greatest design, with an all glass cockpit and the latest heavy shielding. Maybe it would affect an older plane more?

 

[sushi]

Relative Wind

Is that like when my uncle passes gas?

 

[Sdashiki]

All this and I still think I can listen to my iPod on taxi, takeoff and landing with no ill effects on anything around me, including the plane itself.

Alas, the milliwatts of power from an iPod, or CD player, can really have NO effect on anything.

Now a cellphone, yes that can be a problem.

But I have to wonder how people on this thread can say that they had passengers talking while in flight....cell phones cant reach a high flying airplane. there is no signal, sooooo I dont know how people can use THEIR cellphones (not the planes headrest phone) during flight.


Soooo everyone hate me for playing my iPod when they say to turn it off.

I dont care, I stopped flying last month.

never again unless I have to.

flying sucks, plain and simple.

 

[Timepass]

the reason that cells can work in flight is because of line of sight. What is blocking the straight line from the phone in the airplane to a tower.... wait for it....oh yeah noughting.

Now on the ground lets see what is giogn to block your line of sight. You have the curve of the earth so the earth itself is blocking some of it. Building trees and lot of fine partical closer to ground leval. But from the tower it above the heavy dust and particals in the air to begin with and none of that will block line of sight to the plane alone with everything else.

Remember that cell phones use light waves to commincat with the towers. zcell also only put out milliwatts in powers. at most a few watts the cell can not supply more than that.

Just for frame of refrance to show you how far light can go with not block by anything. the light from a match lite match is visible to the human Eye 50miles away. Mind you it would have to be pitch black and clear but still that ammount of light would be visable 50 miles way if it is not block by anything. Cell towers put out even more engery in the form of light than that little match so you get the idea.

 

[matticus008]

Firstly, the idea that pilots stick with planes most of the time is bogus. Large domestic airlines on international routes and at many domestic airports don't have flight crews based out of them--in order to get the crew home, they have to switch flights in the terminal because most planes don't turn around and go back with the crews that brought them. Think about the number of crew members you see in your part of the terminal during the hour you spend there (almost none of them are just hanging out in the terminal--they're there because they're switching planes). Now imagine if almost none of them can get to their planes if the gates are full, and consider the pre-flight work that has to be done, and you can see how a ground delay becomes a major logistical headache.

Short hops can get away with a partial gate service (they may not need fuel or lavatory service and might only need a partial food service and the flight crew might be designated as a noncontiguous continuing flight allowing them to skip the external check) if they're cleared and prepped fully for all segments at the origin airport. But no flight with a crew changeover and needing a full service and (co-)pilot's inspection can be turned around in under 20 minutes. It's just not physically possible on an aircraft servicing 150-400 passengers.

~~~

Elsewhere, relative wind is not the whole story of flight. This is a common misconception by pilots because of how physics involved in flight is explained to them--similar to how beginning physicists neglect drag resistance in their calculations. That explanation of relative wind assumes a constant set of conditions for the surrounding air, a fictional situation.

In other words, the oversimplified explanation linked is good for beginners, but it doesn't explain turbulence or high-velocity crosswind and actually goes so far as to imply that moving bodies don't experience these forces (ever gone up on a bridge while driving and been buffeted toward the next lane? This article would like you to pretend that doesn't happen and that you don't have to adjust your steering to compensate). Relative wind is dynamic as air pressure and direction shifts--disruptions to the laminar flow around the aircraft cause turbulence and aerodynamic drag. The article explains how flight and manuevering work, but it doesn't explain how they're affected by outside conditions or the variables of fluid dynamics. For that matter, it doesn't explain anything about engines or fuel consumption--only about airfoil performance, abstracted away from power generation and ambient conditions. The only thing that page explains is how a plane can experience lift in any wind direction, which has never been denied.

With the clarification that the principles of flight are not exactly the same as the principles of turbofan engines (which are not themselves airfoils) and that commercial aviation is a combination of the two (and more complex physics of interaction), I'm done.

 

[Sdashiki]

the reason that cells can work in flight is because of line of sight. What is blocking the straight line from the phone in the airplane to a tower.... wait for it....oh yeah noughting.

Remember that cell phones use light waves to commincat with the towers. zcell also only put out milliwatts in powers. at most a few watts the cell can not supply more than that.

Uhuh, but I said cellphones cant work in flight. Which using your idea of line of sight, still doesnt work because the recievers/transmitters inside the cellphone cant power it enough to reach any cell tower. But it sure can reach to the cockpit.

And line of sight still isnt a good analogy because I dont have to see the tower to have my cellphone be able to use it. It goes thru walls, cars, bridges....but only to a certain distance.

I refer you to:

If you've read How Cell Phones Work, then you know that cell phones emit signals via radio waves, which are comprised of radio-frequency (RF) energy, a form of electromagnetic radiation.

Thusly my point, Cellphone on a plane, not a good idea.

iPod? why not?

ps: "light waves" = radio waves?

 

[Timepass]

Ok the reason line of sight is so imporant is there is not anything to block the signal or weaken it.

Your right radio waves can go though buildings but when they do it loose a lot of it power. The more stuff it has to go around or though the weaker it becomes. Find a weak radio station in your car that you are having trouble hearing and go drive you car. You will noticed that how bad it gets will change a lot depending on you get near and block you way. drive under a bridge it die quite a bit. or if a building just happens to be in teh way to the tower it will die.

From the Air plane the range of thet cell is easily several times higher since there is not anything to get in the way of the signal to weaken it.

 

[yg17]

I didn't get a cell signal when I was on top of the Empire State Building, how in the hell am I going to get one on a plane?

 

[Chip NoVaMac]

I didn't get a cell signal when I was on top of the Empire State Building, how in the hell am I going to get one on a plane?

LOL, nice one there.

But it may have been cell phone jamming perhaps when you were on the Empire State building.

The line of sight mentioned above does have merit. In urban areas towers may have to be as close as a mile or less to get a decent signal. In the desert it has been said that range can be upwards of 10 miles.

I know that on one SFO to IAD flight, I went to my Treo 650 to check a calendar item; and noticed that I did not turn off the cell phone portion. (Guess I was lucky that I didn't bring that airplane crashing to the earth, and that we seemed to still be on course. ) But I was surprised that I had two bars of signal available. My guess that since we about half way through the flight, we must have been at between 30-35K feet up.

 

[pink-pony115]

wow...for the people that do NOT have the couresty to turn of their iPod or cell phone on a plane is crazy. the flight attandendents are trying to do their jobs...not tell big bubba to turn the phone off. that is just plain stupid to endanger lives on a plane when big bubba wants to yak with mom.
what kind of people are you??????????

 

[belfast-biker]

Not exactly. If I remember correctly, they found that it probably would not affect the plane, but just to be safe they called it plausible/confirmed.

West Wing, Pilot episode...

FLIGHT ATTENDANT 1 [VO]
We ask at this time that you turn off all electronic devices, stow your tray tables and return your setbacks to the full and upright position. We will be landing shortly at Washington-Dulles Airport.

FLIGHT ATTENDANT 2
[approaches Toby] Sir, I need you to turn off your computer.

TOBY ZIEGLER
I’m just about done.

FLIGHT ATTENDANT 2
I need you to turn off your laptop, sir. It interferes with our navigational systems.

TOBY
You know when you guys say that, it sounds ridiculous to most people, right?

FLIGHT ATTENDANT 2
Sir...

Another Flight Attendant approaches.

FLIGHT ATTENDANT 3
Mr. Ziegler? A message was just patched up to the cockpit for you. I’m not sure I’ve got it right. POTUS in a bicycle accident?

TOBY
[stops typing and looks up] You got it right. [reaches for his cell phone]

FLIGHT ATTENDANT 2
You can’t use your phone until we land, sir.

TOBY
We’re flying in a Lockheed eagle series L-1011. It came off the line 20 months ago and carries a Sim-5 Transponder tracking system. Are you telling me I can still flummox this thing with something I bought at Radio Shack?

 

[GFLPraxis]

I've found that the extent is really ridiculous. A GameBoy Advance SP really has no way of affecting anything externally. It has no wireless communications of any sort. Why must it be turned off?

 

[electronboy]

What color of underwear did you want? Low rise or briefs?

We will be forced to listen to these and all other sorts of inane conversations that people have on their cell phones once they permit them on airplanes. If I am in the shopping mall or grocery store I can always walk away from someone screaming "I can't hear you!" into their cell phone, but once you're on a plane you're stuck.

 

[electronboy]

I've found that the extent is really ridiculous. A GameBoy Advance SP really has no way of affecting anything externally. It has no wireless communications of any sort. Why must it be turned off?

What are your qualifications for making a statement like that? BS, MS or PhD in Electrical Engineering? How about Aviation or Aeronautical Engineering?

Keep it simple folks. No electronic devices, no execptions. It's much simpler that way. Unplug yourself from all the digital stuff for just 15 minutes. Its not that difficult. You might even relax a bit.

 

[electronboy]

I didn't get a cell signal when I was on top of the Empire State Building, how in the hell am I going to get one on a plane?

Easy. There is a lot of interference and noise on the ground, but little if anything from stopping the signal from going up. My friend who once was on an airplane stuck in foul weather circling DFW for 2 hours during 1998. Because of the much more fragmented phone system at the time and roaming charges he was shocked to receive a phone bill the next month for over $1,000.

He had a phone bill that was say, 20 or more pages long--with one call taking up 15 pages. Each time he switched to another network the call was handed off and the basic roaming charge applied again. He laughed it off since he was making over 150,000 a year at the time. This really happened.

 

[aquajet]

A GameBoy Advance SP really has no way of affecting anything externally. It has no wireless communications of any sort.

Before arriving at conclusions such as this, it's best to actually know what you're talking about.

Link

 

[tbrinkma]

The choice between 20 mins without music/film and possible risk of painful firey death is not a difficult one.

I'm with this guy!!

Me too. Now shut up so I can watch my frickin' movie!

 

[matticus008]

West Wing, Pilot episode...

The part that bothers me is that the L1011 was discontinued YEARS before the West Wing debuted. The least they could have done was mention a plane actually in production.