Aeons ago, I was F/O on a Dan-Air Bae146 at AMS, closed up and ready to go, tug attached with driver in situ, but no comms via the headset.
We became aware of movement of the 'frame and a heavy vibration as the (solo) driver/crew revved his engine to try to push us back with the Park Brake still ON.
This was followed by a very loud BANG and a lurch as the nose of the aircraft sank towards the concrete, accompanied by the continuous sound of the "U/C not locked down below 160 kts" horn which added to the general air of "WTF!"
Following the sudden miraculous appearance of many spectators staring at the obvious damage and the eventual insertion of railway sleepers with padding under the buckled forward fuselage skin, we disembarked the pax in preselected cabin sections, in order to minimise the total weight shift of disembarkation and possible further sudden settlement.
We found out later the damge totalled £250k (late 1980s money) and the tug driver was found not to have made verbal contact nor had he retracted the towbar wheels IAW SOPs, thereby defeating the purpose of the towbar shearpin.
We were immediately suspended, post accident, so off to Duty-Free and buy some grog for our (now) passenger flight home with another carrier.
The only caution I can take from this accident is the advice not to allow one's hand(s) to appear on/above the coaming at this critical time, just in case the groundcrew, who may be operating with a duff headset or external I/C socket U/S, see fingers tapping impatiently on the coaming and interpret it as the open fist of a "brakes-off" hand signal. Not that that was considered a factor in this case.
