Think HEDGEROW not HEATHROW!


This is a piece from the Flyer Forum  http://forums.flyer.co.uk/viewtopic.php?f=5&t=74173

Hello Iolanthe

Everybody makes mistakes, even very experienced pilots so do not worry about it. Increased life expectancy comes from learning by the mistakes of others!

Grass runways present completely different visual cues to the pilot, especially a student, so it’s not surprising that you had some problems with alignment, gliding angle. and touch down point.

Grass is useful for landing on especially if pre-planned!

Aiming to land on the runway or field threshold is a very bad habit to get into because it can remove your option of safe undershoot at many airfields and if you have an engine failure for real you will be lucky to survive an approach undershoot into a hedge. Once you saw the aircraft was aiming for the threshold you should have commenced a go around yourself (that was your major error)- if there is any doubt, there is no doubt, GO AROUND!

Trying to stretch the glide is a common problem. We teach aiming for the far end of the runway, clean and then bringing the aiming point back with flaps to a point one third the way down the landing runway.

We also teach increasing the best glide speed by 10 kts on base leg. This allows a greater safety margin on the finals turn and also keeps 10 kts in hand to correct any undershoot on final. (this is non standard and you should follow the advice of your own instructor)

Most students and many instructors, fail to realise that best glide speed is also Vmd, in other words the bottom of the drag curve. Once the speed goes below Vmd you become speed unstable and you need much more power to recover the airspeed and the ROD will increase dramatically, another reason for our + 10 kts. If you are flying a glide approach at Vmd you must ensure that you are flying the speed spot on.

If your tarmac runway has ice on it I would also expect the braking action on the grass to be poor. Any runway with poor braking action needs special attention and care, if not avoidance!

This advice from the CAA via their excellent safety sense leaflets:

Short wet grass should be treated with utmost caution, it can increase landing distances by 60% – it’s like an icy surface! Take account of all of these most carefully and then add an additional margin for safety before deciding. (Safety Sense Leaflet No. 7, ‘Aeroplane Performance’, recommends a 33% safety factor for take-off but 43% for landing.)

If you already have ice on it you may see why I would be very cautious!

From what you have posted I would recommend that you develop your situational awareness alongside your technical skills, as you progress. There tends to be a major concentration on technical skills in PPL training with not enough attention to SA. Knowing when and how to fly a go around is much more important than making a good landing.

Grass strips are great to fly out of but there are many traps for the unwary, have a look at these safety sense leaflets

http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode=list&type=sercat&id=21

Strip Sense
Aeroplane Performance

And remember the poster advice, THINK HEDGEROW not HEATHROW

Fly safe!

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