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Training videos

Started by Britjet, Tue, 3 Feb 2015 17:23

Holger Wende

Thanks to you all for the explanations!  :)

Maybe another video wish: "Take-off, climb and level-off...".

Particularly the transitions between rotate, lift-off at 6s and reaching v2+10 after 9s...
I wonder whether flying a reasonable TO is worth an extra video.
And I would be suprised if I really meet these numbers during most of my take-offs.

And a while ago I manually flew TO with AT engaged, climbed stable, all fine, but when I wanted to level off I had real problems stabilizing the aircraft at the target altitude until I disconnected AT.

The Circuits videos explain many manual flying phases really well but levelling off with AT engaged does not seem to be trivial (for me)... Probably just another beginners error.

Regards, Holger

Hardy Heinlin

Hi Holger,

when the A/T is in SPD mode, you shouldn't fly manually -- unless you make just very subtle control inputs.

Your manual pitch movements will not only vary the vertical speed; it will also vary the airspeed (the higher the pitch, the lower the airspeed), and the SPD mode will try to counteract these airspeed variations: These counteractions in return will move the pitch even more, and the situation becomes unstable.

This is because the engines are mounted below the wing, below the lateral axis of the aircraft. Thrust increase or decrease causes the aircraft to rotate about this axis.

Thrust modulation is another kind of pitch control. So it also influences your transit from and to level flight.

You raise the nose, the airspeed drops, the SPD mode adds thrust, and this thrust increase raises the nose even more.

You lower the nose, the airspeed rises, the SPD mode reduces the thrust, and this thrust redcution lowers the nose even more.

Generally, when you fly manually, you should also control the thrust manually. When you change from climb or descent to level flight, or vice versa, the main thing is to change the thrust, and there is only little to do with the stick.

Example (PW engines):

Load: Basic 008 - Climbing above 10000 ft.situ

Disconnect the A/T and the A/P and F/D. You're in a stable climb. Now, to level off, reduce the thrust to circa 1.11 EPR. The nose will drop automatically. Now use the stick to hold a pitch of ca. 4°. You're in level flight. Use the stab trim to remove the stick pressure.

When trimmed and stable, start the descent by reducing the thrust to idle. The nose will drop automatically. Now use the stick to hold a pitch of ca. 1°. You're in a stable descent. There's not much to trim, if at all.

Now level off by adding thrust to circa 1.11 EPR. The nose will rise automatically. Use the stick to hold a pitch of ca. 4°. You're in level flight.

Now start a climb by setting CLB thrust. The nose will rise automatically. Use the stick to hold a pitch of ca. 8°. You're in a stable climb. Use the stab trim to remove the stick pressure.


Cheers,

|-|ardy

emerydc8

Good examples and analysis, Hardy.

QuoteAutothrottle use is recommended during takeoff and climb in either automatic or manual flight. During all other phases of flight, autothrottle use is recommended only when the autopilot is engaged.

FCT 747-400 at 1.34 (Oct. 31, 2008).

I usually hand-fly it to top-of-climb (or close to it) with the a/t engaged (THR REF||VNAV SPD) and then engage the a/p so I don't have to fight the pitch oscillation described above. When descending out of 10,000,' I like to click the a/t and a/p off, unless we are doing a VNAV approach or a Cat II/III where the a/t is required.

I've seen a lot of guys, though, who use the a/t for every hand-flown approach and then click it off around 100.' I presume this habit starts out with good intentions, in an environment that encourages use of all the automation that wasn't always there on the 747 classic and definitely wasn't there on the DC-8; but over time I think this causes pilots to pay less attention to airspeed on approach -- they just expect the a/t to keep them safe (like Asiana did in SFO).

I would add that use of autothrottles on a three-engine approach makes it twice as hard to fly due to the asymmetry and the pitch oscillation. Of course, on a two-engine approach, you won't have them anyway.

cagarini

Although not directly connected to what's being discussed in the last posts of this thread, I did some experiments with PSX's accuracy on asymmetric thrust.

Using the SITU that starts at cruise, I started to shutdown #1, and applied the required rudder correction to coordinate and slightly bank towards #4, used rudder trim to compensate, stabilized, then repeated with #2, then #3.

As #3 was shot down I noticed that the amount of rudder ( trim ) compensation required was inferior to the scenario of two engines shot down on one side :-)  . Restarting #3 required again to use some more rudder, and then rudder trim, to compensate adequately.

This looks great, and coherent.

The only thing that still surprises me, under these scenarios as well as under some approaches is how "poorly" the 744 bleed off speed on descents, even when spoilers are deployed to their max inflight position.

Using ATC, an external robot not the built in, I sometimes am brought to high to my FAF, and from there on it is really a pain to bleed of speed and altitude ... It is under this circumstances that I really miss the 744 not being my glider, where a good deal of sideslip can do miracles :-)

As a final note, PSX ( and I don't recall the same being modelled so "intensely" in PS1 ), revealed how pitching moments due to wider throttle variations really play an important role when hand flying an approach or a training circuit :-)

emerydc8

QuoteUsing ATC, an external robot not the built in, I sometimes am brought to high to my FAF, and from there on it is really a pain to bleed of speed and altitude ... It is under this circumstances that I really miss the 744 not being my glider, where a good deal of sideslip can do miracles :-)

You should never trust VNAV to make sure you are able to get down. Always have a VOR tuned on the field, in the FIX page, or use the ILS DME. Every 1,000' multiply 3 x your altitude. If you are at 300 knots on the descent, add another ten miles to that figure. Contnue to compare that figure with your actual distance from the runway as you pass every 1,000' on the descent.

If ATC keeps you high, then you need to speed intervene and start slowing in anticipation of them giving you lower. If you are high, but slow, you can trade the speed for altitude to get down. But if you are high and you haven't started slowing and/or configuring, it's going to be hard to get down once they give you lower. I think using speed brakes on the descent is basically an admission that the descent planning was screwed up, unless ATC intervened somewhere and caused you to be high.

400guy

I don't think side slipping would be a good idea in a 747, and FOR SURE not in an airbus!

cagarini

Thx for your posts emery and 400 :)

Yes, the sideslip was just a glider pilot comment :-)

Regarding VNAV accuracy, I believe that I started learning about it's limitations long ago, but I had forggoten about it and when I bought PSX and started using it, again, I was surprised to find out that most of the time it used to get me to high, or too fast ...

The same applies to the PMDG 777 my other Boeing airliner sim.

IRL, I spent some good time travelling in the cockpits of not only, but mostly, Air Portugal flights, and noticed how very often they start their speed and alt intervention , including manually setting the V/S...

As a former user of Airbus add-ons for flight simulator, I was surprised during my first flights in the jumpseat on their real counterparts to observe the pilots setting the V/S of FPA manually soon after T/D, and specially during approach, as well as disengaging the A/T and A/P at the FAF.


emerydc8

It's probably been posted here before, but I think this Children of the Magenta video provides a good analysis of automation dependency.

https://www.youtube.com/watch?v=pN41LvuSz10


J D ADAM

A magnificent presentation.  Disproves the "dog and pilot" scenario.

Cheers

emerydc8

"Click Click, Click Click"

cagarini

Superb !

Thx for sharing!

Britjet

New video uploaded - available at the top of this post...

"Non-Normal Procedures 1 - EICAS". This is the first of 3 tutorials on generic Non-Normals.

Enjoy!

Peter


emerydc8

Excellent presentation, Peter. Thanks!

Jon D.

744

Hi Peter.

Any thoughts on how I create an 'Anti-Skid Fault' at say, 2000agl as a stand alone fault? I note the CB is outside the flight deck.

Kind Regards

Steve.
macOS BigSur V11.4

Hardy Heinlin

There are several possibilities to create an antiskid fault, but they will create other faults too. E.g. you could fail all three IRUs or all four DC busses, and that would fail all eight antiskid cards No. 9 to No. 16. This will trigger the message ANTISKID OFF (which inhibits the message ANTISKID).


Cheers,

|-|ardy


If there is serious interest, I might add an antiskid fault item on the Instructor's malfunction pages in the next PSX update.

744

|-|ardy

Thanks for the quick reply. It's an item in my next company check. It's a popular sim scenario failure as minima below CAT IIIA is not approved, auto brake system inoperative etc...and would require a G/A to check the Inflight Performance section of the QRH.

Personally (IMO) it would be a great addition to the Instructors malfunction page.

Thank you for the program, its very much appreciated every 6 months!

Regards

Steve.
macOS BigSur V11.4

cavaricooper

Peter-

Many thanks, mate! For those of us who have ambled the hallowed halls of the 744 at an enforced distance ;) your presentations take all the knowledge gleaned from pouring over FCOMs, SOPs, FCTMs etc, and solidifies it into certainty.  It's rather nice to finally "know" I've been doing it "right" as opposed to just meandering through carefully discerned rote.  The subtleties and finer nuances of your layered explanations are absolutely icing on the cake.

From the colonies... Happy Thanksgiving :)

C
Carl Avari-Cooper, KTPA

Kabbers

Thanks Peter, we're non-normal and proud of it w00t!

Really appreciate first the explanation then being able to actually watch you navigate around the EICAS notifications and CANC/RCL buttons like this Peter, as you trigger faults. Looking forward to the next episode on integrating EICAS with QRH sequences - cheers mate, brilliant.

uninhibited best wishes :)
Kabbers

Britjet

Thanks guys, and best wishes!

Peter

John H Watson

Peter, regarding "32) Non-Normal (NN) Procedures 1 - EICAS
https://youtu.be/TH85aoHoKlA33)"

You say that Status Messages are inhibited after start until 30 minutes after takeoff. My manuals say that only the Status Cue is inhibited (includng the BA Maintenance Manual).

Is this a new option?

Thanks
Cheers
JHW