The 80 knot call - potential for confusion?

[wellthis]

Airplanes are certified at all weights to abort at the published V1 and come to a safe stop in the condition given for that certification, not just dry VRF days and experienced crews. Plus any crew that is rated on a type should be qualified to operate it. Not to mention that the reject made with all operating engines would provide reverse and more stopping force as you know.(as in the case of our discussion)

Now if a pack trip-off light comes on at 100 kts, sure probably better to continue; but should we detect a malfunction which could potentially be deeper than we think(ADC) at low speed, why not stop and have a look. From personal experience of losing ADC on arrival on a VFR DAY, so many systems are lost that would make it safer to abort on TO. We all have done low speed rejects in the sim, often times you have to add power again to make it to the TWY!!

[Blacksheep]

Most of the above scenarios assume that an Air Data failure would be detected at 80 knots [i.e. low speed] or that an aircraft can safely be controlled in flight without airspeed data. Remember that altitude data may also be missing or corrupted. The last time I was involved in an incident involving a Pitot Static failure the PF identified the defect when he noted that the aircraft was well down the runway and going 'fast' yet he hadn't had an 80 knot call from the PNF. The pilot elected to continue the take-off, and in fact a rejected take off would have been much faster than 80 knots. [From examining the raw inertial groundspeed data later, about V1 in fact]. He made it back on the ground where the pitot head covers were found not to have been removed. On the aircraft type in question the static ports are seperate from the pitot probe but on other common rating types in the fleet the static sensors are on the probe and altitude data would also have been absent.

Don't discount the importance of a compromised Pitot Static system. The Air Data Computers supply data to so many other systems in current aircraft types that the total effect can be extremely confusing.

**************************
Through difficulties to the cinema

PS. On another occasion I observed an aircraft taxi past and turn onto the runway with a pitot cover in place. When I phoned the tower I was scolded for wasting their time as the aircraft was "only positioning to the stand" That won't put me off doing the same thing again though!

[Skyking]

Re : HUDSON

Hudson , RE :" I have never seen a call made when the ASI is less than 80 knots " ......


Hi , just in reference to your statement , in our organisation we do incorporate an " Airspeed Alive " call which is shown as 50 kts on our ASI in the beechjet 400 that we fly in addition to the 80kts call. If as stated in your hypothetical situation that either one of our ASI's are reading incorrectly , it would be possible to pick up the 20 kts difference in reading. On the other hand , it may be a little more difficult to pick if the discrepency is smaller in magnitude.Just a thought.

Cheers
SK

[quid]

80 knot check

In my fleet, we operate at a very large range of V speeds. The lowest I've had lately was 104 and the highest 144. That's a range of V1 speeds of 40 kts. It's too simplistic to try to make a "one size fits all" rule about what's considered "high speed" and what isn't.

We do use an 80 kt. crosscheck and call, (and I've picked up a few other ideas here), and it seems to work for us.

On a test flight a couple of months ago I was in the right seat. I called "80 knots" on mine, and glanced over at the Capt's and it was showing zero. He was a little slow in aborting (I know he didn't want to) so we applied the brakes around 100 knots. At the very light (empty) weight, we weren't even 3000 feet into the takeoff roll, so getting it stopped was very easy.

As was noted by others on this thread, inoperative airspeed readings may lead to other problems in the air. I'd rather keep it on the ground. An abort at 80-100 knots is no problem.

[Hudson]

Quid. "An abort at 80-100 knots is no problem".

I agree. The problem arises if afterwards you are on the carpet with a please explain in front of a government flight operations inspector - or a commercial manager who wants your guts for garters for frightening the passengers with an abort - because you used your good judgement at the time - whereas Mr Boeing states that above 80 knots is considered a high energy abort and that it is not recommended unless for fire, engine failure, take off warning or you think it won't fly. I have witnessed court cases where the lawyers use the manufacturer's manual to hang someone out to dry - regardless of the decision of the pilot to vary from recommended procedure.

I prefer to work on the theory that if you have thrust (good acceleration), your take off performance sums and flap setting are right, and a serviceable artificial horizon or more, then with correct knowledge of attitudes for various speeds, it is safer (in general) to sort out the problem in the air.

The reason that I first started this subject was because I have seen several "incidents" in the simulator where crew confusion has reigned momentarily (5-15 seconds) when the 80 knot call has revealed a serious ASI error - or misread. I believe that the subject should be amplified in simulator briefings and the solutions thrown open for free discussion.

And by the way, reading back through my old 1976 B737 Boeing manual (nice to read original thinking rather than the carefully worded, dumbed down prose of modern manuals), the 80 knot call was purely an airspeed check. It was not an incapacitation check per se. That was added in as an after thought by some companies.

[maxalt]

If modern pilots had the ATTITUDE/POWER basic skill like back in the time, a blocked pitot would not be such a big deal, and certainly not a reason to die.

LEM you made two posts in this vein. I think you are being a bit harsh on modern pilots.

By modern pilots (like the guys in the Birgenair 757) I guess you are referring to pilots who spend most of their time flying Glass Cockpits with sophisticated Flight Directors and Autopilots?

Do you know that (as per manufacturers recomendation) the SOPs at many airlines require crews to use the FD all the time, and Autopilots most of the time? Who can blame them for losing the basics of Pitch and Power flying? It isn't being taught and it is not being required of them!

However, not just 'modern' pilots have crashed aircraft through basic instrument failure. I remember this Northwest Orient accident in 1974...on a 727. Icing caused erroneous airspeed increase on climb which the crew misinterpreted as being real...resulting in a fatal stall. You can hardly say those guys were misled by modern cockpit philosophies?

I experienced pitot icing during descent in cloud some years back and it was an ass puckering moment, and no matter how good you think you are I defy any pilot not to be momentarily shocked and disoriented when he sees his airspeed rocketing upward and overspeed warnings ringing in his ears. It takes a massive effort of logic over instinct to resist doing something very stupid and deadly.

[DanAir1-11]

IMHO, despite the fact that you are indeed accelerating rapidly, you would still be comfortably below V1 and as such a STOP command would be prudent, given that the abort would be fairly a relatively tame affair. I would personally err on the side of caution.

[Menen]

Just out of simulator and observed reaction when 30 knot airspeed error intoduced into captains airspeed at press of TOGA on take off. RH seat handling. Left seat calls 80 knots - RH seat said "What! mine is just passed 60" am aborting" LH seat says "Negative - no abort above 80 unless fire, failure - continue". In view of ealier contributions to this subject it was most illuminating - the hestitation and confusion that is.

[maxalt]

The fellow who wanted to press on didn't remember the full story.

1. Engine Fail/Fire (a non-supressed Master Warn)
2. Any event/failure which might make the aircraft unsafe/unable to fly.

...including airspeed malfunction IMHO...as I said earlier.

[LEM]

maxalt,

"LEM you made two posts in this vein. I think you are being a bit harsh on modern pilots.

By modern pilots (like the guys in the Birgenair 757) I guess you are referring to pilots who spend most of their time flying Glass Cockpits with sophisticated Flight Directors and Autopilots?

Do you know that (as per manufacturers recomendation) the SOPs at many airlines require crews to use the FD all the time, and Autopilots most of the time? Who can blame them for losing the basics of Pitch and Power flying? It isn't being taught and it is not being required of them!"





I don't give a damn **** about SOP's when they tell me not to be a PILOT!
Can you imagine a bus driver who knows how to push buttons but not to drive anymore?

I'm used to this subject: I'm always been the one who pushes for hand flying (no FD, no FMS, nothing) - although able to push buttons very well.

To me it's a kind of religion, and has turned into a sort of mission: my copilots know that their (almost) only opportunity to hand fly is to fly with me, and they know they don't even need to ask to disconnect everything.

I have noticed how bad their skills have become, now that all is required from them is filling papers and pushing CDU buttons.

Retaining good basic handling skills is a MUST, not only to be a real pilot, but above all to be a safe pilot.
Not only you can better monitor the automatisms, but for sure time will come when you will have to rely solely on your handling skills.
I'm deeply convinced official training is insufficient (today as in the past), and one has to train himself when the conditions are easy: raw data circling approach at the minima, not at the turistic altitude of 1500ft, NDB approach instead of ILS... and so on, all done in CAVOK, simulating bad weather, that's valuable training, instead of pushing a stupid button which even my dog would be able to push.

With that background, when you'll have to make a circling at night, low ceiling, under the rain etc... that will be a piece of cake.
When I was a copilot I've seen incredible things from the laft seat!

If only the passengers knew!!

I'm not gonna waist time enumerating all of them, but it's a shame!

So, going back to your post, those (Asian?) companies mandating the use of autopilot are just one of the aberrations of our time, where the man is dying everyday a bit more and turning into a little alienated robot.

CRM has become the only magic word, and you end up with three incapable ****** , although very experienced, killing everybody for a faulty ASI, instead of being able to say FU** the good manners, level off and give it a handful!

I'm gonna stop here.
Sort of disgusted?
You bet!

Who can blame them for losing the basics of Pitch and Power flying?

I do.

[maxalt]

Sorry LEM, I couldn't read that post...too much effing and blinding.

Get a grip.

[Smokie]

LEM,
I couldn't give a tinkers cuss about the language but basically you have hit the nail on the head.
Far to many guys and gals relying on Auto Pilot, FMS etc.

When the chips are down and all you've got is a "basic" but very Heavy Areoplane, then God forgive them that can't fly the afore mentioned Aeronautical Ironmongery to a safe and happy conclusion.








And High above the Albatross, hangs motionless upon the air..............

[Idunno]

Both LEM and Smokie seem to miss the point.

Airlines have SOPs that dictate automation.

Anyhow, if you 'fly' Airbus, disconnecting the automatics does not mean you are 'handling' the machine in the way you did with a geriatric jet. The computers are always there between you and the flight surfaces. There is no real flying of such aircraft, you point them and they go! There is no 'feel' to the flight controls. No feedback. No trim.
What exactly does this trick prove?

The only way to truly 'fly' an Airbus 'manually' is to switch off the FACs and go Direct Law.
Not a good idea on a revenue flight.
This is why they invented simulators.

In addition, disconnecting everything might be fun if you fly around the desert in CAVOK without another bird in the sky. Its just not a wise move when operating in a high workload two crew environment in congested airspace, so most never get the opportunity anyhow.

[LEM]

Idunno, I have expressed my opinions on the alienating nature of the FBW Airbusses on several occasions (see the "Airbus shock" thread for some fun... ).

Your point regarding congested airspaces is a good one, of course, but fortunately many of us stll fly both to congested airspaces and places with little traffic.

May I decide by myself if it is safe to hand flying, or do I need a writted rule for everything?

My blood pressure is still high when I think about pilots unable to fly the aircraft in a goaround, killing hundreds of passengers because they are completely lost without automation - or because the automation is screwing up.

SOP's didn't save those passengers.

And that's only one example.

[SR71]

Great thread!

[b777pilot]

i don't give a damn **** to SOPs'??? good show old chap! that's telling them how you have conducted your flight-deck!!

ah yes, if only the passengers knew. indeed.

[Captain Stable]

SOPs can never cover all eventualities. Sooner or later you will have to operate outside them. Logic dictates that you should get all input you can before making your decision, and you should then (if at all possible) brief the people concerned - FO, CC, ATC - whoever.

I would be disappointed in a company whose SOPs stated that the aircraft should be flown FD/AP on/engaged at all times. I would also be disappointed if they didn't stress that pilots should keep all their skills brushed up at all times - not just when the next Base Check is looming. Someone who doesn't know how to operate all the automatics in a skillful and professional manner is being as cavalier as the person who can't fly without them.

In the example given above, of the automatics taking you into harm's way, the fool who blindly allows the automatics to continue to do so will die a fool. Clearly that is not a case within the intentions of this thread.

Another point needs making - which is that, particularly at altitude, a human being, no matter how proficient simply cannot fly a modern high-performance aircraft as smoothly, as economically or as proficiently as the automatics can. Anyone who thinks he can is deluding himself.

There are right times and places to practise your skills and there are wrong places to do so. It is important not to get them confused. It is also incumbent upon us to keep all our skills up to date.

[LEM]

Well said, Captain Stable.

I don't know for sure, but if there are really companies mandating the use of autopilot at all times , that's very sad.

What I've seen personally, instead, is that airlines encourage in their SOPs their crews to fly raw data at least once every ten sectors.

That's also sad, to see pilots have become so lazy, they need to be pushed to keep up their basic skills.

And it's a bit pathetic to see these pilots disengaging the autopilot only the day before their sim checkride.

[Hobo]

Blacksheep,

I think the history of the 80kts call dates back to a tailwheeled Boeing bomber (B17?). It was the speed that the pilot pushed the control column forward to get the tailwheel off the ground. This tradition (as well as using the same style of control column) continued with every Boeing aircraft thereafter.

It certainly is a Boeing thing, on a British civil jet with more than two engines but less than 4 we called 100kts.

[7p3i7lot]

Hobo,
Great post. The Boeing theory sounds very plausible to me. If anyone has a refutation I am all ears.