L-12A Electra accident in Belgium
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L-12A Electra accident in Belgium
Lockheed L-12A Electra Junior, NC14999, damaged in a landing accident at Zwartberg (genk) in Belgium 01-07-18.
https://www.luchtvaartnieuws.nl/nieu...isch-vliegveld
Locked brake?
https://www.luchtvaartnieuws.nl/nieu...isch-vliegveld
Locked brake?
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At 1:41 in the video, the rudders can be seen moving well to the left, and remaining in that position as the aircraft changed heading. It is common for taildragger pilots to apply swift and large rudder deflections to maintain the desired heading on the runway, with the obvious intent to not allow the aircraft to drift off the centerline. An uncorrected heading change past a certain angle could reach a point at which a groundloop is likely.
I'm no tailwheel pilot myself, but knowing a bit about the mechanics, a left rudder input could be appropriate to counteract gyroscopic effect when the tail comes down. That's just one of the issues of course, there's also P-factor, crosswind and I'm sure there's even more in this list.
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Presuming the throttles were both closed, there would be little P factor, nor gyroscopic effect. Those are factors during takeoff. Any wind seemed pretty small, as the aircraft did not appear to be being flown so as to compensate for a crosswind. The brisk application of rudder occurred late in an otherwise pretty straight rollout. Tailwheel planes are unforgiving of heading excursions on the runway.
Just to satisfy my curiosity, isn't the severity of any gyroscopic effect also influenced by the mass of the prop(s)? A heavy metal prop rotating at 1000 rpm will still give you some gyroscopic effect, although significantly less than at take off.
(as I said, I'm no expert, but I am curious...)
(as I said, I'm no expert, but I am curious...)
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I cannot speak for the Lockheed Electra, I have not flown one. The DC-3 has a locking tailwheel, as it is otherwise free castoring, so of no use for steering, the rudder (and perhaps brakes and differential power) do that. That said, the tailwheel does little to control the direction of the aircraft until it is firmly planted on the ground, and the aircraft is moving so slowly that the rudder(s) have little aerodynamic effect. The DC-3, and seemingly the Electra, are wheel landed normally, so the tailwheel is not doing much at runway speeds anyway. I was trained to never three point a DC-3 (Basler Turbine), and never assume that the tailwheel will hold it straight, that's the pilots job on the pedals. It is noteworthy for this event, that the rudders can be seen to move well to the left before the tailwheel touches, the rudders are controlling the direction of the plane. Even after the tailwheel is down, the tailwheel would not be doing much to overcome the effect of the application of rudder, until the plane slowed to the point where the rudders had no effect.
The gyroscopic effect of the tail lifting or settling is there, though at low power easily overcome with correct application of rudder. A few knots of crosswind gust would produce more effect than the gyroscopic effect in most taildraggers.
The gyroscopic effect of the tail lifting or settling is there, though at low power easily overcome with correct application of rudder. A few knots of crosswind gust would produce more effect than the gyroscopic effect in most taildraggers.
Yes, the tailwheel does lock, not to say it was locked for this particular landing though. Had the opportunity to ride this one a number of times as a very young teenager, pilots being friends of the family.
VH ABH is a great aircraft. I did my initial twin initial tail wheel when it was VH ASV with a total time of just 125 hours
Always remember we use to have someone outside with a fire extinguisher just in case we got an induction fire on start up.
Always remember we use to have someone outside with a fire extinguisher just in case we got an induction fire on start up.
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I am really sorry to see this happen to such an iconic plane, the type that Amelia Earhart disappeared in. I am glad everyone inside was ok. To me this accident has nothing to do with P factor or gyroscopic precession. The aircraft was under good control until just after the tail wheel touched down. It then veered rapidly left. This is about the time the brakes would have been applied, As mentioned above it could have been a locked (left) brake but if this was the case it would have continued turning left whereas it straightened up after it turned towards the hangar. It is more likely to have been a failure of the right brake so when left brake only was applied it veered left. To increase the left braking would have aggravated the groundloop leaving the pilot with very few options.
I hope it can be repaired ok. Good luck guys.
I hope it can be repaired ok. Good luck guys.
