Any idea if that particular Tiger Moth had its leading edge auto slots either fixed closed or previously removed altogether? It is a cost saving measure used by some civilian operators. All RAAF Tiger Moths had operating auto slots which gave excellent pre-stall warning by the noise of them opening and shutting with a noticeable `clacking noise`
While there was only a few knots difference in stalling speeds slots locked or unlocked, it was part of pre-take off checks in RAAF Tiger Moths to have the auto slots unlocked. It is understood the Tiger Moth operated by the RAAF Museum and which crashed during practice engine failure shortly after take off had its auto slots either disabled or removed altogether, thus depriving the aircraft of an effective stall warning.
