Being winter, I have gone through several de-icing procedures lately. In Detroit, I noticed there was a De-Icing frequency. What is that for? I assume it's another frequency you need to change to when in the de-icing area. Along those lines, I was de-iced in Dallas last week and I assume they don't have that frequency. How would you communicate there? Also, that pilot mentioned every airport had different procedures, i.e. shutting engines down, etc... How would they be different? I figured they would all have the same de-icing procedures. Thanks!

Most places have a separate frequency for the de-ice pad, and some places have multiple de-ice pads, each with a discrete frequency (I think MSP is one of those).

When approaching the de-ice pad, we switch to this frequency and establish contact with the supervisor there. At some places we call it "De-ice control" and many places call it "Iceman." Iceman will ask us to confirm that we are configured for de-icing before they start spraying. This normally means engines shut down with APU running and the air conditioning packs off. Some places will conduct de-icing with one or more engines running, but they need to be aware of that for obvious safety reasons.

Once the de-icing is complete, Iceman will give us the following information:

• Time at which the final application of fluid began
• Type and concentration of de-ice fluid (e.g. "Type 1, 50%")

He will then clear us to start engines and depart the pad. We use the information provided by Iceman to consult Holdover charts to determine how long we have to get airborne (this varies depending on fluid type, concentration, temperature, type and strength of precipitation). If we exceed this Holdover time, we can still depart, but we have to first conduct a visual inspection (one pilot will actually go back in the cabin to look at the wings).

I'm not sure about Dallas, but in cases where they don't have a separate radio frequency, the supervisor at the de-ice pad will connect a headset to the external comm panel on the nose of the plane and talk directly to the pilots. This is the same thing that the tug driver does every time we pushback from a gate.

Any differences are minor. Some places are adamant that engines can't be running during the spraying. This creates an issue if the APU on the plane isn't working. With no APU, you can only shut down engines at the de-ice pad if they have a huffer cart (external source of pressurized air) at the de-ice pad to start an engine.

How does a turbine engine start up?

I am just...flabbergasted. I mean, really. Wow.


LGA is like 10-15 miles from JFK am I right? What the heck were you doing at FL 190 15 miles from the airport? Also, ooooo- 4500fpm!! that would still take you a bit more than 4 minutes to get down and by then you would be in the Atlantic Ocean! ALSO, wouldn't this rate of descent be very difficult on the passengers with regards to their ears popping? Final question: Is the 250 knot rule really followed? One of my CFI's told me that ATC can only see your groundspeed on the radar, so would they have any way of knowing your indicated airspeed?

Just in case my sense of humor is not understood, I am just busting your chops. I am sure there is something I am missing or overlooking or not understanding.

O yea, if you are ever in New Orleans, PM me- I'd love to buy you a drink. I go to school at Tulane and uptown New Orleans is a cool place.

No problem with the chop busting and I'll clarify a few points.

On this arrival, we usually end up going well past the airport (over the Atlantic) before turning back to land. Getting to ten miles out over the water is not unusual. They have to keep us high over Long Island because of the way they have the airspace allocated for arrivals and departures from several airports in the area.

We didn't actually drop the gear until we slowed to 250 kts for the 10,000' restriction. Above that, we got a good descent rate by lowering the nose until we were right at barber pole on the airspeed (probably ~330 kts). The gear can't be dropped until we're below 270 kts.

As for the ears popping, the pressurization system prevents that by controlling the cabin descent rate. By the time we're down to 10,000, the cabin pressure is already down to almost sea level and it's not that noticeable to most passengers because it doesn't exceed a 300 fpm rate of descent for the cabin pressure.

Your CFI is right, but you have to keep in mind that everyone on the controller's scope is flying in the same mass of air, so planes going the same direction should have roughly similar ground speeds. If you're flying 280 instead of 250, you'll stick out like a sore thumb. Of course, if you're the only guy on the controller's scope he won't really know because those kinds of winds are quite possible just a few thousand feet up.

In spite of this, the speed limit rule is really followed by us in the airlines (can't speak for corporate pilots, but I'm pretty sure they adhere to it also). But if I see 255 on the airspeed, I'm not going to panic because, as you point out, they can't see airspeed on the controller's scope. I will just slow it down to 250 and not worry about it.

Every once in a while (pretty rare) you'll hear a controller query a particular plane, e.g. "November Two Two XRay, say airspeed." This is a subtle hint that this pilot is cheating on the speed and the controller's on to him.

The exception to the 250 kt rule is when we are in international airspace. For example, coming back from South America, we are often given a descent to 7000' when we're still about 30 miles out over the Atlantic. Since we're more than 12 miles from land, we can fly any speed we want and we keep it fast until approaching U.S. airspace. (Of course, if the controller asks for a specific speed, we comply. It's still his airspace for control purposes, he just doesn't expect an automatic speed reduction.)


I've been through New Orleans, but never had an overnight there. Everyone says it's a great overnight and I'd love to be able to take you up on this some day. The son of a good friend of mine went to Tulane (Green Wave, right?) and was AFROTC...now flying C-17s.

[p.s. I'm flying the red-eye back to JFK tonight from Vegas and we'll almost surely be on the LENDY5 arrival. I'll try to take some notes on the airspeeds and distances involved in getting down for the approach.]

^Thanks for the reply so quick.

I was always curious about the 250 rule but I haven't really had to worry about it since I fly T-41...errr, Skyhawks. That is pretty cool that outside of US airspace you can go as fast as you want. Trying to be a fighter pilot ehh?

That makes a lot of sense about ATC wanting to keep approaching planes high over New York because of all the other planes trying to land.

Thanks for the info about the cabin descent pressurization as well.

Tulane is the Green Wave, yes. I know a lot of kids in AFROTC. They say it isn't too tough but they have to run a lot. There was a lab science course offered in aircraft engineering but you have to be in ROTC to take it or else I would have been in this thread taking your " more than the minimum knowledge of aircraft systems" to town, just kidding.

If you ever are in New Orleans just let me know. I guess the airline will probably put you in the French Quarter but uptown is a lot better and a lot less disgusting. Thanks again.

Just got back from Vegas this morning. I debated taking the red-eye, but opted on my 6:00 AM flight. Can you offer any pro or cons to the red-eye? As a pilot, do you look more forward to a red-eye vs. a 6:00 AM flight or is it just personal perference for each pilot? Thnaks!

I'm not a big fan of early wake-up calls, so I'm happy to avoid 6 am flights (which probably means a 4 am wake-up). The red-eye flights are pretty nice because there's less traffic and we usually get direct routing...we're often cleared direct to Wilkes-Barre, PA while we're still over Utah.

The only challenge for the red-eye is being well rested for it. In fact, I'm taking a nap right after posting this answer...I'll get about a two and a half hour nap in before leaving for the airport (which is a little less than I usually plan on, but I couldn't pull myself away from the poker table).

Do you usually get a row of red-eye flights for some time and adjust your sleeping schedule like a shift worker or are the flights to long apart / random to even matter?

(I'm asking because if I compensate for early get-ups or such with daytime naps I seem to be even more tired throughout.)

What you get is dependent on how you bid. You can bid a particular type of trip and put a limit on it, or bid for particular days off, etc. For January, I got 6 Vegas trips, all with red-eye flights at the end. That's because I bid for Vegas trips with a minimum layover of 18 hours. (As it turns out, I traded one for a Copenhagen, and another one was canceled due to snow in the east).

You're not doing back-to-back red-eyes, i.e. they're not two nights in a row, so it would be hard to adjust your sleep schedule. I find that if I take a nap before my red-eye (2 to 4 hour nap), I'm fine for the flight home. Tonight I got a 2 hour 20 minute nap, which is near the minimum for what I want.

[p.s. sitting in the LAS terminal typing this. Our plane was late (just pulled in as I'm typing this) and we're due out in 20 minutes. We'll probably be 20 minutes late departing. Gotta go...]

Have a nice flight

Using pressurized air (either from an APU, an external air cart or another running engine), we turn a start switch to open the start valve. When this valve is open, the pressurized air spins the starter which in turns spins the engine core. After the engine accelerates to some minimum rpm, fuel is introduced and igniters (similar to spark plugs) automatically fire causing light off and further engine acceleration. After some minimum acceleration (50% for the 767), the start valve automatically closes and the igniters stop firing.

On some planes there's a push button to open the start valve instead of a start switch and on the latest aircraft the entire start sequence is automatic once the button has been pushed (i.e. fuel and spark are introduced at the proper points).

We did get the LENDY5 arrival this morning and we got very expeditious vectors to Runway 22L. Normally, we slow to 250 kts at LENDY, but the controller told us to disregard the speed restriction and gave us a descent to 8000' (from FL190). I still had to slow to 250 kts as we approached 10,000' and we only ended up getting about 6 miles south of JFK before being turned east on the downwind for 22L. He continued to descend us and turned us on to the localizer at 2000' and about 8 miles out from the airport.

You've told us about the cabin pressurization system before but can you explain why my ears only ever tend to get blocked in descent rather than climb? Seems to be counter-intuitive as the vertical speed is obviously less in descent than it is in the climb.

On a different note, what do you think of this guy's flying skills?
http://users.skynet.be/fa926657/files/B29.wmv

So are you hard on the brakes at this time? Can the engines idle on the ramp without providing thrust? Don't there need to be a lot of hot gases shooting out the back of the engine for it to keep running by itself?

Do all single engine turboprops have an APU then?

For the first engine start, the parking brake is set. The second engine is often started while we taxi, using cross-bleed air from the running engine to spin the starter.

Even idling engines provide some thrust, but unless the plane is lightly loaded it's not enough to cause a stationary plane to move. However, idle thrust is often all that's needed to keep the plane moving once it gets going. Unless the plane is heavy, one engine is all we need to taxi out; at max taxi weight, we sometimes need to start both engines because we would have to increase power on one engine too much to provide breakaway thrust.

Yes, the exhaust is very hot and I certainly wouldn't stand behind a running jet engine.

I should correct myself somewhat. I was referring to jet engines in my explanation of the start sequence. Although a turboprop is also a turbine engine, many turboprops initiate engine rotation without pressurized air, using an electric start motor. That's how we started the J-32 I used to fly.

i think this was covered in more detail many pages ago (zomg this thread) but basically it's because the eustachian tubes (which control the air pressure behind your eardrum) work better one way than the other.

think about diving to the bottom of a swimming pool. you feel pressure in your ears as you descend, even if you go slowly. now you get to the bottom and perform the valsalva maneuver (pinch your nose and blow gently) to equalize the pressure in your sinsues. you can rocket to the surface as fast as you want with no discomfort.



btw, as long as i'm posting in this thread, i'll give w0x0f another thanks: i finally got my ppl back in december after an agonizing month of rescheduling, crappy weather, failing the practical and having to re-test. i'm still kinda glad it's ski season and not flying season here in seattle, but i'm looking forward to spring and summer and taking some trips.

this thread is what inspired me to get my license, as you can read here:
http://forumserver.twoplustwo.com/34...l#post18785830

and i know i'm not the only one. so thanks, w0x0f! you have done an awesome thing for all of us as well as for general aviation.

If you're talking about the plane's climb and descent rates, we often descend at rates in excess of what we can achieve in a climb. I'll often see 3500 to 4500 fpm descent rates (and sometimes up to 6000 fpm), but we rarely climb for any sustained period at greater than 3000 fpm, especially as we get higher.

That's all kind of immaterial, however, as the pressure controller keeps the cabin climb rate at about 500 fpm and the cabin descent rate at about 300 fpm. During climb, cabin air pressure is decreasing and air wants to escape from your inner ear. During the descent, air pressure in the cabin increases trying to squeeze air into your ear. Not a very good description I guess, but this may have something to do with getting that blocked feeling more on the descent.

Wow, really? The thought that I inspired even one person to get their pilot license is pretty cool. I hope you don't curse me later for getting you into an expensive hobby.

First post....

I read the entire thing, all 205 pages. I was a frequent flier until my work situation changed after my boss passed away (not many flights on Delta, though).

Anyway, last Friday, I went to the local airfield and took a discovery flight. It was a blast! If I can pass the medical exam (i have poor eyesight), then eventually, I'll take more flight lessons!

We landed the Cessna 172 in a stiff cross wind- I won't forget that one!

I still have a hard time with the steep banked turns- I keep wanting to lean out of the turn and sit perpendicular to the ground instead of not leaning and going with the turn! I think I'm still afraid of the plane rolling over...

So you went for your first flight last Friday and today (3 days later), you're still having a hard time with steep turns? LOL! Go easy on yourself! Leaning away from the turn is a common tendency in beginners. The innate fear you have is normal also. I can still remember the mixture of excitement and fear from my very first flight in a light plane. A lot of the fear has to do with the unknown and you'll chip away at that over the course of learning to fly.

Keep the pointy end forward and the shiny side up!

My dad got me a flight lesson for my birthday over a year ago, and I've never built up the courage to go. Its obviously a small plane in a local airfield. I was starting to think maybe I should do it, but just read an article in the local paper that 4 planes have crashed since october. are pilots in my area awful? it seems like a lot.. should i be worried to go?

I don't think OP will mind if I answer this one:

NO!!!!!!!!

Agreed. Go for it. I'm not a pilot but wrt OP, flying on a 757/767 isn't really flying, it's getting from A to B. The most dangerous part of the day will be the drive to and from the airport. Enjoy the feel of the air beneath you.