View Single Post
Old 3rd Aug 2013, 07:37
  #77 (permalink)  
Ultra Glide
Join Date: Oct 2005
Location: On the couch
Posts: 15
The Airbus can easily be hand flown BUT it's a tad trickier than "conventional" aircraft (meaning aircraft that you can trim) because you cannot "trim a speed".

Here's a way to visualize the difference between an Airbus and a plane you can trim:

Airplane you can trim: Straight and level, 250 knots, AP, FD, ATHR off, you retard the the thrust to idle, hands off, the airplane descends at 250 knots.

Airbus: Same scenario, you retard the thrust to idle, hands off, the airplane continues straight and level and starts slowing down, increasing pitch attitude to maintain the flight path.

You can think of the side-stick as a "flight path selector". Whatever flight path you have when you release the stick is what flight path the aircraft will maintain (until you exceed the flight envelope but that's another subject).

So, for example, when you're flying around in the terminal area getting vectors for an approach and they tell you descend from FL 100 to FL 60, you have to retard the thrust levers to idle AND make a DEFINITE nose down push on the sidestick to make the airplane go down.

In my MD-80 days all I had to do was pull the power off.

So you make your nose down input, now you have to pay a lot of attention to the speed to make sure you have EXACTLY set the correct pitch attitude to maintain your 250 knots or whatever (the odds of which are slim to none) so WATCH THAT SPEED and KEEP watching it because you will never actually set this theoretical EXACT pitch attitude to maintain the correct speed for anything longer than about a minute or two if you're lucky.

The reverse is also true in that when you add power, you better PULL that nose up, it won't go up by itself like in a "conventional" airplane that is always trying to maintain its trimmed speed.

There have already been at least 2 Airbus crashes during go arounds where the guys failed to adequately increase the pitch attitude and the airplane just went downhill faster and faster when they pushed the thrust levers to TOGA. (There was more to it than that obviously, but it was a major factor.)

One was a Gulf Air in Bahrain like about 10 years ago and the was only a few years ago somewhere in the Black Sea or some inland lake in Eastern Europe or where ever.

Those 2 crashes most likely would not have happened had they been flying airplanes that you can trim because after setting TOGA thrust, the airplane would have pitched up mightily to maintain the trimmed approach speed with TOGA thrust. They would have had to push the control column forward HARD and even trimmed nose down to achieve those flight paths into the water that those guys achieved effortlessly in their Airbuses.

Another thing: the thrust lever travel is shorter than on other airplanes so the thrust appears appears a bit more sensitive but it's not a big deal, you get used to it pretty quick.

So, once you understand the subtle but important differences between flying an airplane that is always trying to fly the last selected flight path versus an airplane that is always trying to fly the last speed you've trimmed it for, hand flying an Airbus, while not quite as easy as hand flying a trimmable airplane, is nothing to fear. Just scan the hell out of your speed all the time.

And that's my 2 cents worth.
Ultra Glide is offline