Sandstorms

[TrT]

I have studied the nature and formation of sandstorms, but it is better to hear from people that have experienced them. So I ask other ppruners for some tips with dealing with them. Bear in mind our operation is low level helicopter work and far away from airports etc. We also do not have very up to date weather reports in our location. If we get stuck we land and sit it out, but being battered in a 2000kg machine with 60km/hr sand is not much fun.

[Flying Bull]

Hi TRT,
I´m not working, where bigger sandstorms happen...
But still, we have thunderstorms, showers and so on.
First, wheather check - today with internet - easily done and a must!
(If you working where no infrasructure is - you should have a satellite-telephone, so that you can call one who can do the weather for you)
Second, if your sandstorms make only 60 km/h - any decent helicopter does at least 100 kts - thats 180 km/h and speed enough to fly around / past a more or less local weatherphenomena.
Becomes hard, if the thuderstorms you want to evade are frontal thundersorms.
Ones was lucky, that radar could give me a clue where to get through - but was a more than 120 nm detour....
Greetings Flying Bull

[uniformkilo]

I found myself in a sandstorm over the deserts of central Saudi Arabia once, in an R44.

Straight and level at about 3000ft agl, in blinding sunshine but otherwise calm conditions, all of a sudden I was surrounded by dozens of huge spinning towers of sand. From ground level to twice my height.

They looked really heavy and laden with energy.

The really alarming thing was that they seemed to move faster than my VNE, though that may have been an illusion. I have a clear memory of looking out of my side window and seeing one of them overtaking me. They lurched this way and that, randomly changing direction.

My only option was to select max rate of climb, and hope to get above them before one or more of them hit me, while turning sharply left and right to keep from being trashed as they crisscrossed my path.

Finally felt safely above them at about 7000ft, where there were no more spinning sand devils, just a sky full of sandy dust, which obscured all visual references thanks to the sunlight reflecting off its shiny grains.

I was back into clear air a few miles later.

I think flying in the cool of the early morning may be the surest way of avoiding the problem.

UK

[Arm out the window]

If you can, have some low visibility recoveries to your base organised - roads, line features of any kind that you can follow are a bonus, with headings, timings at say 60 kt (low vis type speed) organised.
I haven't done a lot of this kind of thing, but flew in Egypt for some months years ago; having an emergency get-home option was good if you were out and a sandstorm looked like it would encroach.

One other thing that sticks in my mind (pardon the pun) is getting significant main rotor vibes seemingly out of nowhere one day, landing to sort it out and finding a very hard accretion of really fine dust / sand particles stuck to the leading edge. Once we'd removed them (took some work), the vibes were gone.

[Flying Foxhunter]

Many years ago in the Sudan, I watched as our 206 was launched skywards some 10 feet into the air without the said pilot. The sandstorm hit so quickly that there was no time to tie the machine down. It was lifted up and then slammed down on its side by a 'haboob'. This was particularly unfortunate as I had just filled it with about 10 old ostrich eggs, which were duly scrambled and I suspect caused a bit of an issue when the machine was eventually returned to Hurn at Bournemouth for a bit of a repair job :sad: