Plane Answers: Wing inspection lights and a recent severe turbulence encounter

by Kent Wien on

Welcome to Gadling’s feature, Plane Answers, where our resident airline pilot, Kent Wien, answers your questions about everything from takeoff to touchdown and beyond. Have a question of your own? Ask away!

Alex asks:

Hi Kent,

I recently flew on a 737 and returned on a different airline on an MD- 80. Both flights were only about 40 minutes long and the wing lights remained on for the duration of each flight. I thought those lights were usually turned off once the plane has reached a certain altitude and/or a certain distance from the departure airport. I don’t remember the wing lights staying on during previous flights. Is it left to pilot’s discretion for these lights or is there an FAA regulation covering when to leave them on?

Hi Alex. It’s up to each airline to set procedures regarding when the wing inspection lights are used illuminate the leading edges of the wings and to provide an extra level of collision avoidance.

At my company, we use the wing lights from takeoff until 18,000 feet, and then again descending below 18,000 feet until turning off the runway after landing. That said, they they may be left off at the pilot’s discretion.

Ron asks:

Hey Kent!

I know you’ve mentioned turbulence several times, but I have a turbulence question. I fly a decent amount, over 100K miles a year, and being a huge aviation geek, turbulence doesn’t bother me, in fact sometimes I like it.

Today in the angry skies over Texas on a flight from Houston to Boston, I experienced turbulence I didn’t like!
As we waited in line to takeoff, I noticed ATC was spacing planes really far apart, and in my experience, that’s never really a good sign. We took off, and minutes later the turbulence started, it felt a lot like being on space mountain, but it didn’t end. The plane would bank from one side to the other, while bobbing up and down. Anything that was not bolted down was flying around. My question is, does this kind of turbulence phase pilots and when, if ever, does it become too much for you?

You’re right Ron, I’ve had a lot of turbulence questions, but it’s a question worth revisiting from time to time.

Most pilots will start looking for a smoother altitude by asking ATC, other airplanes or their dispatch soon after the seatbelt sign goes on. Sometimes, like when flying over the Rockies, it’s apparent that there just aren’t any smooth altitudes available.

As soon as it becomes uncomfortable or annoying to passengers, you can be assured that it’s not much fun for the pilots either. I swear the ride gets worse the moment we get our meal or if we’re writing something in the logbook.

It takes a significant amount, far more than most any of us have experienced, to cause structural damage to an aircraft. That said, if I were in the turbulence you describe, I would be concerned for the safety of passengers and flight attendants that aren’t sitting with their seat belts fastened.

Our options at that point would be to change altitude, change course, or even to turn around and go back.

But of all the things to worry about on a flight, turbulence shouldn’t really be one of your top ten concerns.

I hope your next flight is much smoother.

Do you have a question about something related to the pointy end of an airplane? Ask Kent and maybe he’ll use it for the next Plane Answers. Check out his other blog, Cockpit Chronicles and travel along with him at work.

26 hurt on turbulent Continental flight

by Katie Hammel on

On most flights, turbulence is a minor inconvenience. You have to return to your seat and buckle in, and you may have to wait a little longer to get your next vodka and cranberry (oh, is it just me that needs a cocktail, or three, to relax on a plane?). Planes are generally able to avoid the worst of the bumps, thanks to radar and reports from other planes in the area. But sometimes, turbulence strikes seemingly out of the blue, and that may be when it is the most dangerous.

This could be what happened on Continental Flight 128, which hit severe turbulence on its way from Brazil to Houston and was forced to make an emergency landing in Miami early on Monday. The plane encountered the turbulence just northwest of Puerto Rico and landed at Miami shortly after 5:30 a.m.

The turbulence was so rough that it catapulted passengers from their seats, slamming them into luggage bins and bashing their heads into overhead seat controls, cracking the panels and breaking glass in the reading lamps. 26 people were injured. Four of the injuries were reported as serious and 14 people were taken to the hospital.

Passengers stated that the turbulence didn’t last very long, and that after it had passed everyone remained calm. There’s no word yet on what exactly caused the turbulence, but the FAA is investigating.

[via ABC News]

Seven injured as Qantas Airbus slams passengers into the ceiling

by Scott Carmichael on

A Qantas Airbus A330-300 flew through what airline staff referred to as a “severe meteorological incident”.

The “incident” was actually bad turbulence, and it was so severe that the plane plummeted, sending passengers into the ceiling.

The flight was en route from Hong Kong to Perth when it hit the turbulence. Because the drop was so sudden, the flight crew did not have the time to warn passengers to be strapped in, though it does underline how important it is to have your seat belt buckled at all times.

It isn’t hard to see some similarities between this flight and the recent crash of Air France flight 447 – especially since both were on the exact same type of plane.

Planes often rely on information from other aircraft on the same route to report on turbulence, but if the route is not very busy, it may be hours between reports.

Bad turbulence can cause severe injuries, a collection of some of the most recent incidents involving bad turbulence can be found in the gallery posted below:

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More crazy stories from the skies

Plane Answers: Turbulence causing aircraft to break apart and London holding patterns.

by Kent Wien on

Welcome to Gadling’s feature, Plane Answers, where our resident airline pilot, Kent Wien, answers your questions about everything from takeoff to touchdown and beyond. Have a question of your own? Ask away!

Tai asks:

Hi Kent,

I’m an avid reader of both your blog and Plane Answers and plan to pursue a career in aviation.

I generally keep an eye out in my news feeds for airline/aircraft related stories and came across a CNN article about an Air France A330 which was lost over the Atlantic. Officials are saying that the crash could have occurred as the plane encountered extremely heavy turbulence.

Is it possible for turbulence to be severe enough to actually cause a plane to come down, or would there likely be other factors or problems with the aircraft? Also, if there is turbulence that strong, wouldn’t the captain reroute the flight around it?

I’m often questioned about the dangers posed by turbulence and I’ve explained in the past that modern airliners are engineered to handle the worst case scenarios. But there are absolutely situations, such as extremely large thunderstorms that could cause structural damage to an aircraft.

It’s a big part of why airlines, and pilots specifically, are so concerned about accurate weather reports, good radar technology, flight planning and operating procedures that keep us away from thunderstorms.

Our manual even specifies a 20 nautical mile distance to be flown around thunderstorms. But don’t confuse every cumulous cloud as having the potential of a thunderstorm.

One of the few examples of an airliner being brought down due to turbulence that I’m aware of hits rather close to home for me. In the late 1960s the airline my grandpa had started 40 years earlier purchased a competing airline.

Just weeks after that purchase, one of the recently acquired airplanes, a Fokker F-27s broke up in-flight near Illiamna mountain after an encounter with severe-to-extreme turbulence.

It was the worst accident by far over the 60-year run of the company. So while I’d love to say turbulence could never cause an accident in a modern airliner, I wouldn’t rule it out as a possibility today.

But I’m not so sure that’s what happened to Air France 447. In fact, by definition aircraft accidents are usually the result of something rather unanticipated. So I don’t buy any speculation by the analysts at this point, even with the small clues the ACARS maintenance status messages give us. This is the stage of an investigation where nothing is ruled out.


Jackie asks:

Hi Kent!

What a great service you do here. I have read through numerous posts and it has surely helped calm some of my fears of flying.

A few months ago, I was on a BA flight from PRG to LHR and about 30 minutes outside of London, the captain came on to tell us that due to heavy traffic volume, we were to be placed in a racetrack holding pattern. This holding pattern lasted about half an hour before we began our final descent to LHR. As someone who is a very nervous flyer, anything out of the ordinary makes me very on edge. I’ve flown a great deal, but this was my first experience with a holding pattern. I guess I have been fortunate!

My question is: Just how common are racetrack holding patterns? Are some airports (such as LHR) more notorious for holding planes in that way? Also, I was curious as to whether there is any type of “hierarchy” for exiting the holding pattern? I mean, is it truly first-in, first out? Or since we were in a smaller plane (737 or A320) for the short hop from Prague, would preference be given to the heavies coming from the USA and such?

One final question, when we were in the holding pattern, and in the midst of a turn, the plane quickly jolted/banked to the side in which we were turning and then quickly jolted to the extreme other side as if the pilot quickly corrected this. He then came over the speaker to say that we had hit an air pocket. Does that sound right? Is there any danger in “hitting air pockets” while in a holding pattern turn? I do remember we were pulled out of the pattern to land soon after that experience.

Hi Jackie,

Holding while on the arrival portion of a flight is probably more common in London than any other place I’ve flown. I’d estimate that half the time I have flown into London involved a hold, usually for only one to three turns.

The priority is based on first in, first out. So you may start holding at 16,000 feet and be given lower as the airplanes below you clear out. Finally, at perhaps 11,000 feet, you’d be the next one in line and could then start the rest of the approach.

You almost certainly came across another airplane’s wake. You can think of these currents that are generated by aircraft much in the same way a boat creates a wake as it plows through the water.

In your case, there was probably an airplane holding at the same altitude that had been cleared lower and your flight began holding at that level as well. The wakes usually descend as time goes on, which can be an issue when holding below another aircraft.

Since the holding patterns drawn and flown by the airplane’s computer known as an FMS (flight management system) is so precise when coupled to GPS technology, it’s no surprise that you happened to come along another airplane’s wake.

Generally, they’re startling, but they don’t threaten the safety of airliners.

Coincidently I have a video that shows a flight we did last year as we were about to enter the London holding pattern over “OCK” or the Ockham VOR which is a specific point we navigate to near the town of Guildford. Notice the holding pattern drawn by our computers for our airplane to follow.

In the third to last scene, you can see the airplanes on the screen that we can view in the cockpit. And the final scene shows us selecting a lower altitude before I put the camera away.

Thanks for the great question.

Do you have a question about something related to the pointy end of an airplane? Ask Kent and maybe he’ll use it for nex
t Monday’s Plane Answers. Check out his other blog, Cockpit Chronicles and travel along with him at work.

Plane Answers – A pilot’s experience before flying solo, a passenger pointing out a mechanical problem and wake turbulence bumps

by Kent Wien on

Welcome to Gadling’s feature, Plane Answers, where our resident airline pilot, Kent Wien, answers your questions about everything from takeoff to touchdown and beyond. Have a question of your own? Ask away!

Esteban from Spain asks:

When learning to drive a car, for most people a few minutes of training are enough to drive, although they don’t know the circulation rules. Do you think that it is possible to take off, turn, and land in a small cessna with few hours of training without obeying the navigation rules?

Hi Esteban,

Soloing is the moment every student pilot dreams of. That moment when your instructor hops out of the airplane and tells you to take it around the ‘patch’ three times.

Can it be done in just a few hours? Absolutely. But you’d have to find an instructor willing to put his certificate on the line at that point. The ‘typical’ range is anywhere from 6 to 25 hours, but that’s also dependent on the airport you’re flying from and the type of airplane.

Densely populated areas have more requirements for ATC communication and airspace regulations, so your instructor will want you to be familiar with those regulations before letting you go.

For a more anecdotal look at the typical times before soloing, take a look at this thread written by flight instructors and pilots about the subject on AirTalk.org.

Cassandra asks:

I just flew down to FL from Hartford last Thursday on Delta and had a window seat on the wing. Just before we began our descent, I had glanced down on the wing and noticed 3 round tanks(?) that were screwed down right by the emergency door. What caught my eye was the fact that 2 of them seemed to be leaking what I thought was water or some sort of clear liquid. It was 2 smaller tanks near the front of the wing and a larger one just behind them. The two smaller ones were the ones that were leaking and all coming from under the screws. It was enough they were trailing down towards and past the next tank.

What are these and though it might have been nothing, should I have said something to the crew after the flight? Of course it was dry by the time we arrived at the gate.
Hi Cassandra,

It’s common to see slight stains around some of the screws on the wing, especially on the bottom of the wing near the fuel pumps. I’m sure what you saw wasn’t critical, but I’d encourage you to let the pilots know as you deplane. If you were really concerned about something, bring it to the attention of the flight attendant. They’ll pass it along to the pilots who can then decide if it’s a serious enough problem.

I always follow up on the comment with maintenance, which is often at the gate shortly after we arrive anyway. It’s just a good idea to take even the smallest comment seriously. Many of them can be easily explained away, but it’s always prudent for us to look at anything that’s a concern to a passenger just to be sure.

John asks:

Hi Kent,

Recently, while on a flight from the east coast to the west, we were enjoying a smooth ride. Then, without warning, we hit a pocket of extreme turbulence. What made this differenct was that it was less than 2 seconds, and had the “feel” of an impact.

My questions are:
1) Is this a normal thing, and
2) Does it pose any danger to the flight.

Thanks!

Hi John,

The way you’ve described it, I’m pretty certain your airplane flew through the wake turbulence of another jet. This doesn’t happen often at all, but when the airplane is in just the right position relative to crossing traffic, it can be startling. It happens so briefly that we don’t usually see any injuries, but it will sure make you tighten your belt while sitting.

You can rest assured that the airplane is designed to handle the wake structurally and it generally doesn’t present any danger to the flight.

That said, ATC goes to great lengths to provide enough separation between aircraft during arrivals and departures. It’s during this time that wake turbulence can present a greater problem for airplanes, since the wake is generally larger when jets fly slower, with the gear and flaps down, than while in cruise flight. If the airplane weighs over 250,000 pounds (usually anything larger than a Boeing 757), then the pilots will call themselves a ‘heavy’ which reminds controllers that extra separation is needed behind those aircraft.

Do you have a question about something related to the pointy end of an airplane? Ask Kent and maybe he’ll use it for next Monday’s Plane Answers. Check out his other blog, Cockpit Chronicles and travel along with him at work.