off topic. Pitot tubes

[Coyote Chris]

you guys are the smartest guys I know and this question has been bothering me. Lets say I am flying an airliner across the Atlantic and my pitot tube(s) froze up. No more IAS. The auto thrust control and auto pilot then turn off. How many other ways does a pilot have to measure air/ground speed. GPS? DME?

[Ron101502]

Re: off topic. Pitot tubes

OK, I'll go out on a limb here and will get a lot of flack.

BUT after hours spent in straight and level flight one should know what the normal pitch attitude is and every airliner I have flown ( Have not flown the A-330 but have flown captain on the DC-9, MD-82, B-727, A-320, DC-10, 747-400) it is always about +2.5 degrees of pitch. Most pilots know the normal power seting IF they are somewhere near optimum altitude. Yes, GE/CFM engines use N1 to set power and Pratts use EPR but the Pratts still will have the same N1 at normal cruise altitudes. The 747-400 will always have about 88% N1 at cruise near optimum altitudes.

So when things don't "look right" you can not depend on just a single source of info to see what is really happening. If the airspeed indication isn't right or the stall warning is going off, but the pitch is giving a level attitude, altitude is pretty stable and the power is set right then maybe the airspeed indication is wrong.

Simple, right? NOT!!!!

Night, turbulence, fatigue, maybe being higher than optimum trying to top weather, lots of issues that "airmchair pilots" don't consider.

Add to this the fact that the Airbus flight control systems in theory never lets the airplane exceed the stalling angle of attack (airplanes don't stall because of lack of airspeed, it's because of excessive angle of attack as Bob Hoover always demonstrated in his Shrike airshow) the only way that could happen is an unusual event such as severe turbulence that forced the flight control laws in to a degraded mode that would allow the pilots to stall the airplane. (I think it's called upset law, I haven't flown an Airbus for a decade but the only protection available is G envelope protection in that situation).

All my FOs are either retired military or learned to fly 25 yrs or more ago but I jumpseat to work with some "new kids" who obviously came out of a "pilot mill" school where they have never even been upside down in an airplane. I went through jet upset school a few years ago and they predicated the biggest loss of life in the next few years will be "upsets" or stalls.

Then we had Colgan and of course it's pointed out the guy was weak, but several fatal accidents over the years have been proven to have been preventable with basic stick and rudder flying, although I probably shouldn't have said rudder since the guy trying to fly an A-300 like a Pitts killed himself and his passengers but out of that we learned what parameters airliners were certified under that none of us never knew.

I digress but it looks as though when those kids in the Air France 330 lost it instead of unloading the wing they got a PFD or windshield full or dirt and pulled up aggravating the stall (initial indications is they pulled up to slow down due to high airspeed readings that probably kicked the autopilot off and resulted in a stall even though the airpseed read high). Maybe the result of training to either avoid stalls or minimize altitude loss by "powering" out of the stall (which only works at low altitude if at all) rather than recover from a high altitude stall. Or they did'nt even recognize they were stalled becuase of a high airspeed reading, would be nice to have AOA data supplied to the pilot like military aircraft do.

Stall recovery seems so elemental, I couldn't solo a J-3 Cub untill I could recognize stalls and recover from them, it seems that is a "lost art" but at least Randy Babiitt, the first real pilot to head the FAA in a long time, is aware of it and changing training for pilots. I just did sim training last month and for the first time in several years we did stalls which were pretty boring to us old timers but apparantly a problem for youngsters.

I suspect the end result will be pilot error that was induced by incorrect airspeed readings resulting from pitot tube icing. But these kids were never trained to recognize or deal with such an issue. Remember in France airplane deaths are criminal events so Airbus and Air France will lawyer up and blame the crew. And all the "glass" airplanes I have flown have stand
by backup round guage instruments, we never train to use them. (The only time I've ever been challenged to use backup instruments was my captain checkout in the Convair 580, my instructor, John Mohr {yes, THE John Mohr, famous airshow pilot} failed my primary instruments and made me fly an NDB approach under the hood, this in the real airplane, I actually made it but I admit I no longer have those skills).

I know learning to fly is very expensive but I think all these flight schools should require at least 10 hours of aerobatic training and candidates should be able to hand fly (with no auto throttles) raw data ILS approaches and non precision approaches with an engine out
in the simulator which was required of me as a new hire DC-9 FO in 1977.

OK, fire away, I'm over 61 and still flying 747 captain and you all think I should just go away and let you move up the ladder. Wish I could but that's a topic for another day. I'm not "better" than the young guys but I sure as hell had better training and experience before I sat in the right seat of an airliner. Hope we fix that, I intend to ride with you guys when I retire.

Post has nothing to do with air racing, but I will be at Reno for my 22nd yr, at least we have the love of the sport in common.

Ron Henning




,

[shorebird]

Re: off topic. Pitot tubes

The Airbus is a odd bird. It was designed to be easily operated by low time pilots in developing countries. Great idea but difficult to pull-off. I thought it was one of the toughest type ratings I've ever received. During my brief encounter with the jet, I found it to be very counter-intuitive from a pilots point of view and my classmates, all 20 yr + airline pilots, thought the same. The interface between the ECAM (glass telling you whats wrong) and the QRH (paper telling you how to fix it) was very confusing to me and seemed ripe to cause errors at critical times when pilots need clarity. Boeing, Douglas and Lockheed Abnormal Procedures by comparison, are pretty straight forward and fairly easy to work through.
Ron suggested in his post that poor piloting skills was a factor and I have to agree but, the concept of flying skills and Airbus Flight Control Law is not seamlessly compatible. You don't pilot the Airbus, you manage it through autoflight and it's internal Flight Control Law. The Bus was designed to be flown on autoflight from 400' after TO until touchdown. So, it stands to reason that if a Pilot voluntarily takes the airplane into a flight condition that is beyond the capability of the autoflight system, intervention by the pilot to save the day may not always end well. I'll also point out that to fly a modern automated glass airliner well via autoflight you first have to be competent at hand flying the airplane. Having said that, the autoflight system can be a great flight instructor as to how to fly the jet, if you pay attention, particularly in VNAV.
I would add that the Capt needs to pick the appropriate time to leave the cockpit for inflight rest, flying toward giant thunderstorms at night was a poor choice. I expect that if the Capt had been in his seat this accident likely would have been avoided.

Dennis

[Randy Haskin]

Re: off topic. Pitot tubes

All my FOs are either retired military or learned to fly 25 yrs or more ago but I jumpseat to work with some "new kids" who obviously came out of a "pilot mill" school where they have never even been upside down in an airplane. I went through jet upset school a few years ago and they predicated the biggest loss of life in the next few years will be "upsets" or stalls.

Personally, I think this degradation in the "airmanship" required out of potential airline pilots these days is the greatest threat to safety.

The fact that there's such a thing as "upset school" (and that not everyone even goes to it!) is sad enough.

Everyone should have done baby acro before they're ever allowed to haul people around for money.

[Randy Haskin]

Re: off topic. Pitot tubes

I'm not "better" than the young guys but I sure as hell had better training and experience before I sat in the right seat of an airliner.

As a follow-on, what is really sad is the defensive knee-jerk that people get when this is mentioned.

People don't want to hear it.

Here's an example from a post on another pilot forum that I read, an answer to a guy asking a question about the fastest way to get his ratings.

Because the ATP requirements hit on August 1, 2013, you must have 1500 hours by that date and also have passed the ATP written and practical in order to carry passengers on a 121 airline. There are no grandfather provisions on this. Right now you can still get hired with 250 hours and build the time while being paid. That is what you need to do as quickly as possible. The reason for this is because you will be gathering those 1500 hours on someone elses dime if you are employed as a commercial pilot. As you can see there is a HUGE difference in $$$ between 250 hours and 1500 hours. If you wait to get hired then you will need to have the 1500 hours which you will have to pay for on your own.

This is someone advocating that a pilot go get a job as an airline pilot so they can GET EXPERIENCE. Unbelievable!!

[Coyote Chris]

Re: off topic. Pitot tubes

Thanks guys...very interesting. Is this failure something that would as a rule be given in a normal simulator checkout?

Chris who misses his PA28

[Ron101502]

Re: off topic. Pitot tubes

To elaborate the normal Airbus flight control laws are supposed to make it impossible to stall the airplane so something external (turbulence) is the only way to put the flight control computers into a backup law that allows a stall to occur. Pilot error can not produce that condition, only severe external factors or some sort of malfunction.

Having said that today's pilot training does not provide the skills necessary to overcome such a situation. Randy Babbit has said as much in his proposal to mandate stall recovery and unusual attitude or upset recovery in airline training programs. Only problem is no simulator can actually reproduce such scenarios, they certainly can't replicate the G loads some upset recoveries require.

When I went through jet upset school in the variable stability Lear a few years back the instructors thought that upsets would be the biggest cause of accidents since the introduction of EPGWS on airliners makes CFIT accidents almost impossible. I remember three crash scenarios they cited where the airplanes were recoverable except the crew freaked when the windshield filled with dirt and instead of unloading the wing they tried to pull the nose up and crashed in a fully stalled condition. One was the ATR-42 that stalled due to icing conditions but was recoverable. Another was only recoverable with a little more altitude and a couple guys did in the simulator, that was the USAir 737 wake turbulence upset near either PIT or PHL, probably not enough altitude to recover but the crew again pulled when they should have pushed. I forget the third one but Colgan is another example. The instructors said that most of the time when "text book" pilots go through the program they freak and get totally disoriented in the aerobatic Bonanza which you fly before the Lear as opposed to those of us who, even though we haven't been upside down in 20 yrs have no problem as I spent 6 yrs upside down every day in the USAF. Our biggest issue was trying to pull 2.5 Gs, it felt like 4 as I hadn't done that in over 20 yrs at the time. But we knew instinctively to unload the airplane regardless of attitude when it was about to stall.

Those Air France guys were sold short on their training, not their fault, but in order to protect Air France and Airbus I bet the findings will come down harder on them than it reallty should although if turbulence caused the initial upset one wonders if the crew could have taken another route but that's a real iffy situation that's a discussion for another day.

By the way my airline changed all the pitot tubes on our A330s right after the accident.

Ron

[stuntflyr]

Re: off topic. Pitot tubes

Thanks guys...very interesting. Is this failure something that would as a rule be given in a normal simulator checkout?

Chris who misses his PA28

No. It's something that you would be trained on while getting your instrument rating. I've never gotten partial panel training in the airline scenario. However, we've talked about it in CPT training and did all of the instrument switching while in the CPT.
Chris...

[stuntflyr]

Re: off topic. Pitot tubes

As a follow-on, what is really sad is the defensive knee-jerk that people get when this is mentioned.

People don't want to hear it.

Here's an example from a post on another pilot forum that I read, an answer to a guy asking a question about the fastest way to get his ratings.



This is someone advocating that a pilot go get a job as an airline pilot so they can GET EXPERIENCE. Unbelievable!!

It's OK Randy, 1 civilian hour is about the same as 4 military hours.
Chris...

[FuryFan]

Re: off topic. Pitot tubes

About a month ago I met a couple of British pilots that fly for Thomson, and I asked if they had a preference between Boeing or Airbus aircraft and before I even finished the sentence their answer was, "Boeing". These guys had 20+ yrs experience and they said the interface between the system and pilots on Airbus is more of a hinderance than anything else.......


Kevin

[Big_Jim]

Re: off topic. Pitot tubes

I've been keeping out of this conversation because I don't have any airliner experience, nor do I have any instructor experience....but I do have to say that in the big picture I am shocked by what passes for 'flight training' these days.

At the risk of sounding like the proverbial "..back in my day..." crusty old pilot, I can't believe the p.c., 'hold-your-hand-through-it' type of training that I hear goes on these days. Partial panel? We did that ALL THE TIME in the military...and it was not simulated, it was real...circuit breakers pulled, instruments turned off...so you had to use what you got. Unusual attitude? Again, all the time. You close your eyes, instructor gets the airplane all out of whack, has you open your eyes and lets you get it back to normal. And it pays off too...I got rolled inverted in the traffic pattern once at about 1000 feet....and just rolled through it to recover. No harm, no foul...but the point is, I instinctively knew what to do...didn't have to think about it, just DID it. I got caught caught in the wake of a JAL 747 once and my Skypig dropped like a rock...but knew what to do because we had been trained from day 1. I had instructors literally shut the engine OFF...not just pull it back to flight idle, but cut the fuel off and say "ooops....whatcha gonna do now?", just to see how I would react and what I would do next.

I kind of echo Hacker's sentiment about suggesting going TO the airlines to build your hours....it should be the other way around. But as I said...I'm not a player in the game, so I can only armchair and Monday morning quarterback.

[Coyote Chris]

Re: off topic. Pitot tubes

FYI
AIR FRANCE 447 -- HOW DID THIS HAPPEN?
(http://www.avweb.com/eletter/archive...ll.html#204730)
The pilots of Air France Flight 447 flew the aircraft into deep stall
at 38,000 feet, never verbally acknowledged or corrected that
condition, and the aircraft fell for more than three minutes at nearly
11,000 feet per minute into the Atlantic, killing all aboard,
investigators said Friday. The jet maintained a nose up attitude --
along with an angle of attack greater than 35 degrees -- throughout a
descent rate that translates to more than 122 miles per hour of
vertical drop. "At no point" on the cockpit voice recorder "is the
word stall ever mentioned," Chief Investigator Alain Bouillard said in
an interview. The autopilot and auto-throttle disengaged and the
pilots recognized failure of the Airbus A330's speed sensors. The
pilots took manual control and the aircraft climbed. A stall warning
sounded as the jet ascended rapidly from 35,000 to 37,500 feet and by
38,000 feet three stall warnings had activated. Less than two minutes
after the autopilot disconnected, the aircraft was at approximately
35,000 feet, with full takeoff thrust selected. The angle of attack
had exceeded 40 degrees and jet was falling at about -10,000 ft/min.

http://www.avweb.com/eletter/archives/avflash/1920-full.html#204730

[Scotty G]

Re: off topic. Pitot tubes

Hi Guys,

Mind if a current A319/320/321 driver pipes up? Lots of interesting comments on this thread! Let's get started:

Stunflyer is right; one civvie hour = 4 mil hours! (Love ya, Hacker!)

Ok, seriously...

I agree strongly with some of the comments made about experience and training THESE days. Those comments would not hold water 20+ years ago when I was already a private pilot. Just saying I had some damn good training, and people were hard on me. I didn't *like* it, but I sure appreciated it!

I paid that forward, and ended up getting the shaft for it.

Case in point; I was a company instructor at a freight-dog outfit in San Diego. I was training a new hire in the Cessna 210. I put her under the hood and had her do some maneuvers, then gave her a vacuum failure. "Ok," I said..."Show me on the chart where you are, and pick up IFR back to Montgomory..." I was going to have her shoot multiple approaches.

She baaaaarely did that after I hinted, hawed, and just about told her she was about to hit cumulous granite. She didn't choose to use numerous resources at her disposal.

"ATC will help you, but you have to ask them first." I was trying to see if she would circle (hold her position), triangulate off VORs, find the minimum safe altitude in the area, then climb to it. No, she set a heading for a mountain because the airport was on the other side of it.

I saved her life, and she complained to the boss. Some of THESE people are now flying YOUR airliners. Nice, eh?

When I flew for Argosy out of BUR, I would be single-engine and partial panel the ENTIRE flight from 100 AGL after takeoff. James would give me intentional vectors into terrain all the time to make sure we would never let that happen. I sweated that training so much I was skinny. But I was an alive skinny, and so far so good.

Regarding the 'Bus... I'm tired of the Boeing/Airbus BS. They're airplanes, they work a certain way, and that's the way it is. Get over it.

If you went from a Jetstream to an Airbus like I did, you don't know any better about how the Boeing/Lockheed/Douglas FMS systems work. You just learn the Bus. Done. I did it, so it's not that hard. Now, TODAY, our Boeing guys coming over get SEVEN sim sessions to the 28 that I had. They get a WEEK or two of transition training when I had one month.

I'm a FO, and I have to be an instructor with new Bus pilots. This is not an Airbus problem, this is a safety culture problem because airlines are cheap. I actually like being able to share some knowledge with fellow pilots and add to the safety sum.

Rant over...

"Loss of Reliable Airspeed" is what we've been trained for after the AF accident. It's not all that hard, and I'm not even a SuperPilot. The same thing could happen in a Boeing, Lockheed, Douglas, etc. This is not a Airbus specific problem per se.

What would you do, Mr. Private Pilot with an instrument rating?

Of course! You set a pitch and power setting you KNOW will keep your butt out of the broiler. Use the attitude indicator or the horizon if you have one. It's really basic, even in a jet.

In an airliner, it will depend on your weight and altitude. The higher you are, the heavier you are, the more critical it is because the "spread" between your MMo (Max. Mach number) and VLS (minimum selectable speed) could be as low as 12 knots or so. So you're ONLY going to be that high if the ride is PERFECTLY smooth. Fo real.

Now... You have three airspeed readouts on the flight deck. Look at them. Which one doesn't fit? It's an AHA moment!

Follow the QRH (see below).

Now, the AF guys were going through weather, and I don't know the weight/altitude conditions they were in. Obviously bad things happened, and it's really unfortunate. My question would be why didn't the PF (Pilot Flying) simply resort to something around +2 degrees of pitch and 73% N1?

I'll betcha an Unleashed t-shirt that's pretty close to the ballpark. The QRH (Quick Reference Handbook, and it ain't that quick!) is a binder you use to find info you need quickly that won't come up on the ECAM when bad things happen. (How's that for a run-on sentence?)

It has a chart with weight vs. altitude and what pitch and power to set. You also need to descend to get into thicker air with a larger airspeed spread. The bad news is they were probably going through thunderstorms by then, and all bets are off. That would be some really tough flying, even for a seasoned professional. (Not saying they weren't otherwise...)

In the end, I'm done being overly critical of other pilots when their mistakes show up on the evening news, YouTube (the B-29 thing) or on these message boards. I don't know ANY pilots that make mistakes on purpose, or do something stupid with mal-intent. All pilots have made some really stupid mistakes, it's just some of us weren't charged for them at the time. We got a pass. That time. I will beg, steal, borrow or buy info to tuck into my hat to save my ass in the future. And if you're flying with me, that'll be your butt, too! WINNING.

Hope that sheds some insight on the original question, and thanks for letting me spout off about training.

[Ron101502]

Re: off topic. Pitot tubes

Still not sure why the flight control system allowed the airplane to stall or what kind of weather they were in. The following article is from USA Today:

Air France crash calls for better pilot training, experts say
By Alan Levin, USA TODAY

As Air France Flight 447 plunged in the darkness two years ago, its pilots had ample opportunities to save the jet. Instead, as has happened repeatedly on airliners around the world, they exacerbated the problem, according to preliminary information released by French investigators.


Divers recover part of the tail section from the Air France jet that crashed in midflight over the Atlantic Ocean on June 1, 2009.

Divers recover part of the tail section from the Air France jet that crashed in midflight over the Atlantic Ocean on June 1, 2009.

The Air France disaster, which killed 228 people on their way from Brazil to France on June 1, 2009, is the latest example — and one of the most deadly — of the biggest killer in aviation: a plane going out of control.

The latest information in the Air France case, released Friday by French investigators, is spurring renewed calls for better pilot training and other measures.

"If this was a technical problem (with the jet), we'd be saying we need to fix this," says John Cox, a former airline pilot and safety consultant who has written on loss of control for the British Royal Aeronautical Society. "There have been those of us in the industry that have been arguing for this for decades."

What is needed is better training so pilots are not as startled and confused during emergencies, and better tools to warn them when their planes are about to go out of control, the experts say.

Plummet from the sky

The French government's preliminary report describes what happened:

The Air France jet's 7-mile plunge into the Atlantic Ocean began suddenly when the jet's instruments went haywire. Ice had blocked the jet's speed sensors; the pilots could not tell how fast they were going. Warnings and alerts sounded almost simultaneously.

In response, the pilots made a series of mistakes, according to the French Bureau d'Enquêtes et d'Analyses, the agency that investigates aviation accidents.

Instead of flying level while they diagnosed the problem, one of the pilots climbed steeply, which caused a loss of speed. Then the aggressive nose-up pitch of the plane and the slower speed caused air to stop flowing smoothly over the wings, triggering a loss of lift and a rapid descent.

They had entered an aerodynamic stall — which has nothing to do with the engines, which operated normally — meaning the wings could no longer keep the plane aloft. Once a plane is stalled, the correct response is to lower the nose and increase speed.

For nearly the entire 3½ minutes before they crashed into the ocean, the pilots did the opposite, holding the Airbus A330's joystick back to lift the nose.

Although the response was improper, it would be wrong to simply blame the pilots without looking at how well they were prepared for the emergency and whether the information they received could have confused them, says Michael Barr, an instructor at the University of Southern California's Aviation Safety and Security Program. "They're sitting there happy, the autopilot is on," Barr says. "Next thing you know, lights are flashing, warning horns are on. There were probably 10 warnings or messages coming to the crew at the same time."

Similar miscalculations and miscues have been common in fatal accidents:

•In the Colgan Air crash Feb. 12, 2009, near Buffalo that killed 50 people, the captain overreacted to a warning that the Bombardier Q400 turboprop had gotten too slow and yanked the nose of the plane upward, the National Transportation Safety Board found. If he had pushed the nose down, the board said, he might have saved the plane.

•On Aug. 16, 2005, a West Caribbean Airways Boeing MD-82 crashed in Venezuela, killing all 160 people aboard, after the jet stalled at 33,000 feet. The Venezuelan government blamed the pilots for failing to recognize that they were in a stall during a 3½-minute plunge, despite alerts from the automatic stall warning system.

•On Oct. 14, 2004, a Pinnacle Airlines jet crashed near Jefferson City, Mo., after the pilots stalled the Bombardier CRJ-200 at a high altitude, the NTSB found. Both pilots died; no passengers were aboard.

Similar accidents killed 1,848 people in the 10 years ending in 2009, according to jet manufacturer Boeing.

Limitations of human brain

It may not be possible to prevent all such accidents.

Corporate pilot Patrick Veillette, who is writing a paper on the subject for the International Society of Air Safety Investigators, says there is evidence to suggest that the human brain cannot grasp what is going on in the most severe emergencies.

Still, Cox and others say stall training has been lacking for decades.

Newer flight simulators can better teach airline pilots how planes respond in stalls, and their use should be dramatically increased, they say.

Responding in part to the Buffalo crash, the U.S. Federal Aviation Administration has proposed improving pilot training.

"If we're going to make sizable improvements in aviation safety, we need to deal with upset recovery," Cox says. "That's where the risk is."

Ron

[Box A35]

Re: off topic. Pitot tubes

They flew into a thunderstorm, a big one too. They did not avoid it, they flew into it.

Something needs to be acknowledged that this was the crews first huge mistake - one they did not have the skill to recover from.