8
$\begingroup$

As I was sitting inside the cockpit of an old AN-26 at the aviation museum, long grounded and no longer flightworthy, sudden gusts of wind outside would sometimes move the control surfaces and make the yokes move around all on their own, spooking visitors with creepy thuds and groans of the hull and acting all creepy on the dark windy day. It seems in the days of old, with mechanical controls, it wasn't just the pilot acting on the control surfaces through the rudder - when attacked by winds, they would feed the external forces back to the yoke through the same system - likely both providing the pilot with important knowledge, and causing trouble by wringing the yoke in his hands.

I wonder how that looks like nowadays in modern planes, where the control is electronic, hydraulic, and a feedback like this would need to be specifically, additionally implemented, as an extra complication of the system instead of being in its inherent nature. Well, is it? Do the yokes of, say, modern airliners push harder on the pilot's hands when entering a turbulence or such?

Improve this question
$\endgroup$
3
  • 1
    $\begingroup$ For fly-by-wire, see this related question. Note that this is not a duplicate as it does not answer the question for hydraulic controls. $\endgroup$
    – Sanchises
    Sep 2, 2017 at 15:02
  • $\begingroup$ This question is vague and the answer will depend upon the responder's opinion of what "modern" means. Plenty of "modern" aircraft are still cable and pulley, so this question could also be considered too broad. $\endgroup$
    – Ryan Mortensen
    Sep 2, 2017 at 22:40
  • $\begingroup$ @RyanMortensen: The current answer is perfectly satisfactory to me - the effect neither dead, nor omnipresent. The fact it's being implemented in some aircraft where it would normally be completely absent - and deliberately (not just for cost savings!) left out in others is just the overview I was looking for. $\endgroup$
    – SF.
    Sep 2, 2017 at 23:53

2 Answers 2

Reset to default
5
$\begingroup$

On some. The Fokker 100 is one, where the aeroforces on the elevator are directly fed back to the pilot. There is a hydraulic actuator helping him, but contrary to the usual solution it is a reversible system where the hydraulics merely amplifies the direct force that the pilot exerts.

The F100 has manual reversion for elevators and ailerons, and it can still be flown reasonable comfortably without hydraulics. The 737 also has manual reversion, but the flight controls are quite heavy without hydraulics - it is about the largest high-subsonic aircraft that can still be hand-flown. Larger planes just have triple redundant hydraulic controls, some with q-feel which artificially replicates the higher air stiffness felt at higher airspeeds. No romantic gusty creaking for those aircraft in a museum.

Improve this answer
$\endgroup$
1
  • 3
    $\begingroup$ The Fokker 100 system is called a boosted system. And force feedback is one of the most important sources of information to the pilot. Designing the control system of large aircraft for manual control is a lost art. Sigh. $\endgroup$
    – Peter Kämpf
    Sep 4, 2017 at 14:11
2
$\begingroup$

In Airbus' aircrafts this kind of feedback does not exist yet. The mechanism of the joystick does not take into account external information and the force and torque to be applied is always the same.

However, they are making a big effort to design new joysticks with a haptic feedback. The main idea is to include different string with a variable stiffness in order to modify the torque and force to be applied on the stick. With this system the pilot would be more aware "feeling" the real situation of the aircraft and could prevent some unsafe situations.

Improve this answer
$\endgroup$
2
  • $\begingroup$ Do older Airbusses with yokes rather than joysticks (A300/A310) use force feedback? $\endgroup$
    – Vikki
    Jan 12, 2019 at 22:52
  • $\begingroup$ Actually since the A320-style side-stick commands pitch and roll rates, the side-stick force mostly corresponds to the force on the control surfaces, because the rates do. It is position correspondence that is lost. $\endgroup$
    – Jan Hudec
    Aug 23, 2019 at 21:03

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .