Hi W0X0F and thanks for the thread, it helped me get over my anxiousness towards flying.

Here's the question: Does it sound strange that we were towed back from taxi way to a gate (not attached to the terminal) for refuelling?

The details: Just today I flew Delta from Amsterdam Schipolli to Detroit (too jet-lagged to fetch the flight number right now, but it was scheduled to depart 10:20). After we were pushed to the taxi way the plane stood still for maybe 15 minutes after which the pilot announced that the controllers are having technical problems issuing take-off numbers (or something of the sort, excuse my memory and also didn't hear everything completely), so that's why we are being delayed.

After some time more the captain announced that there was some paperwork-issues regarding fuelling, which need to be sorted out, but we're fine with our fuel really.

Again, after some more time the captain announced we're being towed to a gate to get refuelling for the fuel we burned while standing still on the taxi way (we had stood there for an hour then).

The refuelling ended up taking approximately an hour, after we proceeded to take off and land happily in Detroit a couple of hours ago.

It all sounded very weird to me. Any thoughts?

The situation with the cockpit door being open for extended periods during flight and a passenger having access to the cockpit (and remaining there for the landing) would be something that could get a U.S. pilot in a lot of hot water. There was a day when none of this would raise an eyebrow; the Captain was king and he ran his ship any way he wanted to. Perhaps that's still the way it goes outside the United States. I always assumed that the rules were similar for other countries, but I really don't know and maybe they're more relaxed about these things.

Same thing for the flight time limitations, i.e. perhaps other countries have less stringent rules. For a two pilot operation by a U.S. airline, there's a maximum of eight hours (gate to gate) between rest periods. The minimum rest period recognized by the FAA is eight hours. (Note that it's not a limit of how many hours they can fly in a 24 hour period.) These rest rules don't apply to flight attendants. Thus we have trips where the FAs fly JFK-LAS and return for a total of nearly 11 hours of flight time. The pilots aren't allowed to do this and must get off the plane in LAS in order to have a rest period.

If you're sure that the pilots on your plane flew nine hours without a rest period then there's only three possible explanations: (1) the rules are different for the country in which that airline is certificated; (2) the pilots broke the rules and thereby risked their pilot certificates and their careers; or (3) it was an augmented crew, i.e. more than two pilots (for which the flight time limitations are different, for obvious reasons).

Although I still have a valid Flight Instructor's certificate, it's been years since I've taught anyone to fly so I may not be the best person to ask. But my preference would be to start with a very simple plane, something like a Cessna 152 or Cherokee 140 with just the basic six instruments: airspeed indicator, artificial horizon, altimeter, turn and bank indicator, directional gyro and vertical speed indicator.

After solo and maybe even a cross country or two, we could move up to a plane with more modern avionics if that is the student's desire.

Basic Six Instruments

Most diversions occur because of weather. Sometimes the destination airport closes temporarily and this causes arrivals to stack up in holding patterns. (Other events can also result in airborne holding, e.g. an accident which closes a runway or extremely strong winds which means all takeoffs and arrival must use the same runway, thereby reducing the amount of traffic that can be handled.) Each crew makes their own decision on when to divert and it's obviously based on how much fuel we have to play around with.

After diverting, there can be a considerable wait for the original destination to re-open and even when it does open, there's going to be a backlog of planes wanting to get in. This can result in ground delays as ATC holds us to await a slot in the traffic flow.

Best case is that the destination never really closed; we just didn't have the fuel to wait our turn in the holding pattern. Even in this case, we must get a new release from our dispatcher who is also handing another dozen or more flights (which may have also diverted if the weather system is widespread; it really gets busy for the dispatchers when Atlanta goes down because of the number of flights affected).

There's certainly going to be some refueling necessary and if the airport has a lot of divert aircraft on the ground, they're all asking for fuel at the same time. This is often the source of the greatest delay.

The V speeds come to us by the company via ACARS; it's not something we generate ourselves using the FMS. The takeoff data will usually include more than one runway (at fields with multiple runways) and will often include data for intersection departures.

Taking off from a shorter runway could result in a lower V1 speed or it might require the use of more flaps. For example, when taking off from Las Vegas on runway 25R, we use 5° of flaps. When using runway 1R (much shorter runway), we use 15° of flaps. The extra lift gets us off the ground sooner and at a lower airspeed.

We will brief a planned turnoff after landing but it's only a plan. I hate ruining a good landing by throwing all the passengers forward in their seats, so I'll go the next taxiway (or in the case of Shannon, continue to the end of the runway and turn around) rather than stand on the brakes.

Here are clips from the 10-9 page (taxi diagram) for Shannon airport. The data in the bottom part shows that taxiway Alpha is 6782' from the arrival end of runway 24. Making this turnoff doesn't require excessive braking as long as the plane touches down right around the 1000' point (normal touchdown point).

Following the flap setting explanation in #3834, is your flap setting always lower for longer runways? I know weight and weather factor into the setting, but it always seems the longer the runway, the longer it takes us to rotate as opposed to the same aircraft type rotating much earlier with a shorter runway. I guess what I'm asking is, why take longer to rotate when you can safely do it earlier in the roll with a different flap setting?

Thanks for your answer W0X0F, would you have said something to the crew as the dangers are extremely obvious?

Would being a pilot have swayed your opinion on what to do in this situation or would you feel more obliged to give them a break?

I did forget about Canadian airports...it's been a long time since I've flown there. I used to go to Toronto and Montreal fairly often and I think we cleared customs at both of those before our flights back home.

That sounds pretty strange to me too. You mentioned "the pilot announced that the controllers are having technical problems issuing take-off numbers." I think this message may have gotten garbled somewhat (maybe you're just not remembering it precisely).

We get our takeoff data ("numbers") via ACARS after pushing back. This is issued by the company, not by ATC, and shows the loading of the airplane (number of passengers, cargo weight, ramp weight, estimated takeoff weight and zero fuel weight). Also included here is the trim setting to be used for takeoff, the flap setting and the V speeds for the runways in use for the current weather conditions.

As for the fuel situation, our flight plan shows the amount of fuel we should have on board and it also shows the minimum fuel we can have on board when we advance the throttles for takeoff. There's usually enough of a pad here that we can be out on the taxiways for over an hour without consequence. Good practice dictates that we don't waste fuel in case of delays getting airborne and this means using only one engine to taxi and starting the 2nd engine when we're within 5-10 minutes of takeoff. It's also why we sometime shut down both engines (and operate using only the APU for air and electrical power) in the case of extensive delays, e.g. a ground stop due to weather.

If in spite of our efforts we get close to min fuel, we have to return to the gate for more fuel. I can't remember the last time I had to do this, but it does happen. In your case, it may be that they actually got close to min fuel or that there was some confusion in the fuel planning which was caught when the final numbers were transmitted to the plane. But this is all conjecture and I have no idea what happened on your flight.

What is really strange is that they were towed back to the gate. I've never been towed back to a gate from a taxiway and I could only imagine this being done in the case of some mechanical problem. I'd love to know the rest of the story. Can you tell me the date and flight number (was it 243)?

That's a very good question.

I'll tell you what I think the answer is, but I have to again point out that I'm not an aerodynamic engineer and you're starting to find the edge of my "expertise envelope." (I welcome input from any more knowledgeable experts.)

Almost every plane I've flown has a "standard" flap setting for takeoff. In the 757/767 it's 5°. In the MD-88, it was 11°. I should point out that different planes have different flap settings available. In the MD-88, the available flap selections were 0, 11, 15, 28 and 40 (28 and 40 for landing only); the 757/767 settings are 0, 5, 15, 20, 25 and 30 (25 and 30 for landing only).

Any time you extend flaps, you increase lift and drag. Without the additional lift provided by the flaps, we'd have to accelerate to an excessively high speed to generate the lift to get airborne. This is unacceptable for two reasons: you need an excessively long runway and you'll probably exceed the max speed of the tires (they're only engineered to be operated up to a certain speed; it was about 180 kts on the CRJ).

So, we use flaps to help us create the lift we need to takeoff at an acceptable airspeed and we accept the additional drag until getting airborne and accelerating, at which time we retract the flaps, eliminating that drag. So why not use more flaps to generate more lift and get off the ground earlier? Obviously we do this in certain cases when runway length or performance data dictate, but we don't make a habit of it because of the extra drag we're also introducing into the equation. This extra drag becomes a concern in the case of an engine failure and we predicate all of our takeoff date on this worst-case scenario (engine failure at rotation).

Of course, we can deal with the extra drag and handle the engine failure, cleaning up the drag as we accelerate, but if runway length and environmental conditions allow it we go with the lower drag configuration that still allows us to get safely airborne. Airspeed is life in aviation (at least for us fixed-wing types) and we'd rather have more of it when we get airborne.

Once again, the disclaimer: I almost sure that what I've written here is true, but it may not be complete.

Yes, that must have been it.

The date was 31.7., a KLM number 6043, operated by Delta. (the flight was originally scheduled to take off - or leave the gate - at 10:35am).

One more thing came to my mind: After having sat in the plane for quite a while refuelling a passenger in front of me asked the stewardess how much more time is it going to take. She answered "Well, he said 15 minutes, but that was 30 minutes ago, so I don't know".

That's all the details I can think of. The flight itself was uneventful.

Thanks W0X0F! So cool of you to answer all these questions!

How do you guys handle the late morning or early morning flight when you are flying at the same horizontal level as the sun? On my last flight when the pilots where getting their meal, I was sitting in the front and it seemed blinding to me. Does visual flying cease to exist during that part of the flight? Similar question to #3838, we were sitting at the edge of the runway and the captain said we had to wait we because they had issues with the computer and scanning our luggage to get the proper weight. We waited for about 10 minutes and continued to the runway. Wouldn't you need to know that before leaving the gate?

Every airplane comes with some kind of sunshade. On some planes, they're very similar to what you have on a car, i.e. they flip down and can be positioned to the front or side. Of course, they're not opaque, just darkened (like sunglasses).

On other planes (like the 757/767) the sunshades sit in a slot by our right knee and they must be pulled out and fixed to moveable attach points on the front or side windows. (Some 767s I've been on have a retractable mylar-like shades for the side windows that can be pulled out from the back of the side window and hooked at the front.)

The shades we have on the 757/767 are often inadequate and if the sun is harsh enough some pilots will augment it by draping paper over the edges to block out the worst of the glare. This probably wouldn't pass muster with a check pilot, but up at altitude in Positive Control Airspace it's not nearly as critical as it would be below 18,000 or in the terminal area. Also, if the sun's that bad you're not going to see anyone out there anyway.

Procedures vary from one airline to the next, but in order to expedite the departure it can be beneficial to begin taxiing out and get the final numbers during the taxi. We recently went to this approach (which American Airlines has been using for years). Occasionally, if the weights look like they might be critical (i.e. we're close to max weight), we'll get a message to remain at the gate for our final data. This is to avoid the embarrassment and delay of returning to the gate to offload people and/or bags. And obviously, if there's any confusion in the numbers (as seems to be the case with your flight), it's got to be straightened out before we takeoff.

Oh, I forgot to explicitly thank you for this: despite having been anxious about flying for all my life, having read this thread of yours I was not the least bit worried anymore despite our plane having strange issues about fuelling before departure.

A year or two ago I would have felt horrible about it, but now I just knew there are so many redundancies in safety procedures that even being towed back to gate for refuelling only reassured me that the safety procedures are working fine.

I am sure there are many who feel the same way.

Questions that came to mind on my last flight. Can a passenger tell if a landing was an automated landing that you said previously has to be performed every so often? Sometimes I can hear the computer call outs for altitiude and was wondering if I would hear anything different for an auto land? When you are the non-flying pilot, it is hard to sit there if you see the other pilot doing something different then you would? I saw a pilot in the jump seat and wondered what he did the entire 3 hour flight? Do they offer any advice or do they have to just sit and keep quite with regards to the flying of the plane? Could they speak up if they felt uncomfortable about something flying related? Not sure if you fly along the East coast or over the Gulf of Mexico, but when I'm in an MD-80 going from TPA to DFW we fly along the coast line. If we are in a 737, we cut stragiht across the Gulf. Does that have something to do with ETOPS? Lastly, similiar to my question previous about rotation and runway distance, is there a certain area on the runway that you have to touch down on no matter the length before you have to do to a go-around? For example, if you were landing on 31L at JFK, it would seem you have a lot of room to play with on the touch down. Does how far down you can go depend on runway length? Thanks! BTW...on the same flight, I saw the FO leave the flight deck and the Captain had his oxygen mask on! It looked a different the one you showed earlier ITT.

This thread has been fun and feedback like this is very gratifying...and was completely unexpected when I started this. I just thought it would be fun to answer a few (maybe a dozen or so?) questions over a week or two.

There's no way a passenger could tell, even if they're an experienced pilot. The autoland usually makes a very passable landing, sometimes a great one. So if you experience a very rough landing, chances are it wasn't an autoland.

The altitude callouts you hear (audible to those sitting close to the cockpit) occur for every landing and they're the same whether it's an autoland or a manual landing.

Only if it's unsafe. There are many different techniques employed by pilots for the various phases of flight and though I sometimes might wonder why he's doing it that way (or think to myself that I would do it differently), I would never say anything unless it's going get us in trouble. I'm sure other pilots have the same thought about the way I do things sometimes.

A jumpseater is briefed on the safety features of the cockpit, if they're not already familiar with them (e.g. the location and operation of the oxygen mask, what's expected of them in an evacuation, etc). The Captain will almost always say something like "if you see anything you don't like, speak up." It's always nice to have an extra set of eyes and ears in the cockpit.

As a jumpseater, you adapt to the tone set by the flight crew. If they're chatty in cruise flight, it can be a very pleasant time exchanging news and gossip about the industry or just chewing the fat on things completely unrelated to flying. I've had the other experience too, where little was said for the entire flight (I think it was a red-eye flight), so I found ways to occupy myself without intruding on the crew.

It probably does. When I flew the MD-88, it wasn't ETOPS. We would fly that plane from New York to the Bahamas and iirc we had to remain within 150 miles of land. It might be even less if the plane isn't equipped with life rafts. Although this map doesn't show distances, you can see that the direct route will put the plane some distance from land for the first part of the flight.



We have to land within the "landing zone" of the runway, which is defined as the first third of the runway or the first 3000', whichever is less. Thus, at LGA, where the runways are both 7000' long, we have to touch down within the first 2333'. A normal landing will touch down right around the 1000' point. If it becomes obvious that we're not going to be on the ground within the landing zone, we are required to go around.

Yeah, that was the old two-piece mask, which had attachable smoke goggles stored in a separate pouch. The mask that is most common today has smoke goggles integrated into the mask. Allow me to model:

wow gr8 thread only on page 20 so far just wanted to leave a comment before this thread gets to big

How does the autoland deal with a crosswind?

I just had my first IFR experience in socal, Concord to KSNA, to KSBA tower enroute, then back to KSNA tower enroute again, then back up to Concord the following day. It was a challenge keeping up with the controllers constantly changing my routing but I had a blast.

During an autoland, the autopilot actually engages rudder control at 1500' agl and from that point it uses proper crosswind technique (i.e. nose aligned using rudder, aileron used to counteract drift due to the crosswind).


Were you actually flying in IMC, or was it just an IFR flight plan? If IMC, that's pretty unusuall for SoCal, right?

Almost no IMC, just the marine layer getting out of SNA and SBA, though the ceiling out of SBA was 100ft overcast with fog. From what I understand the marine layer is pretty common down there. It's the first time I've ever flown south of San Luis Obispo.

I've been saving this one for a lull in the questions, so here goes...

The story:

I was flying a Delta redeye from LAS to MSP about 18 months ago.

The 1am boarding started out uneventfully enough, and I boarded in the first wave and took my seat in the first row of coach. This gave me a good vantage point for some of the confusion that followed. (although I admit I was exhausted and still a bit tipsy, so I dozed through some of this and am reconstructing details based on the subsequent conversations I overheard)

The main cabin was boarding, and apparently one of the departing passengers had a brother who worked for the LAS ground crew. At some point during general boarding, the ground crew member came onto the plane to say goodbye to his brother, and then left the cabin to go home as his shift was over. No one had a problem with this as it was happening, but a few minutes later there was a flurry of hushed conversation among the FAs and then the pilot as they did their best to figure out what the heck had just happened. I got the impression that they hadn't really noticed this guy at the time - maybe another passenger asked about it - and they seemed quite frustrated that the gate agent had let him on the plane at all.

The tension of the moment was certainly made much worse by the fact that the passenger being "visited" was a Somali gentleman - complete with macawiis, shawl, and koofiyad - who spoke almost no English.

So while the powers that be are trying to track down this mystery visitor, the captain announces that there's been a minor security problem, and all of the passengers will have to deplane down to the tarmac, take a bus to the ticketing area of the airport, go through security again, and hike back to the same gate to get back on the same plane. (I think they also rescanned all of the checked baggage.)

If I recall correctly, we took off at about 4am with surprisingly little grumbling or concerns among my fellow passengers. I guess the redeye out of Vegas tends to hold a pretty docile bunch of passengers.

So my questions...

(1) Have you ever had something like this happen?
(2) Am I right in assuming that at least a few people (ground crew worker, gate agent?) got in extremely hot water for this?

baronworm,

did delta offer you any compensation for your adventure? did you ask for any? (cuz i would have.)

I'm ashamed to say I didn't even ask. My only excuse is the "Vegas redeye" effect...

No, I've never had an experience like this. It's not unheard of for an employee to come on board to say goodby to a friend or family member...I've done it myself. But I make sure to identify myself to a crew member and let them know what I'm doing.

From what you relate, it sounds like maybe this was an over-reaction, but I wasn't there and it obviously caused great concern to the crew. If I saw a ground employee (ramp or maintenance personnel) come on board, it wouldn't bother me at all. (Of course, when faced with a koofiyad I might react differently. )