Type rated and flew the BAe146 for several years: A very nicely designed and built aircraft. Lovely and satisfying to fly, although no auto thrust, and a fairly basic auto-pilot, and very basic navigation computer: On "ours" we flew holds into Heathrow the old fashioned way by doing the drift, timing and heading calculations in our head. Good mental practice though.
I did my best-ever landing in a 146 at Heathrow.
All reference to hairdryers or APUs instead of engines get short shrift from me. Redundancy and robustness were what counted, as well as STOL performance. 3 engined ferry's were possible and certified.
To achieve STOL, the wing was designed for high lift, which in turn created sub-optimal drag performance in the cruise. Hence, the economics eventually worked against the aircraft, along with the fuel flow of four engines, once aircraft with more efficient wings and twin engines were developed.
A great British success, though.
@zed3; the howl was the flaps deploying. At a certain point, the gap between the inboard flaps and the fuselage caused a sound to be generated by the airstream which deepened in pitch as the gap got larger with the flap movement.