Sand?
Hmmm well, in flying in the mid-east for over thirty years, I've seen plenty of it.
How to cope.
Well, first of all, just land the aeroplane.
Nothing special, except the vis can be reduced...so use automatic approach/land (autoland for you European folks), if you have it.
Works just dandy in the 'ole Lockheed tri-motor.
Engines?
On some occations, I have seen 'em washed out by the fire brigade, there was so much sand.
Strange, but absolutely true.
Other aircraft systems need attention, too.
Especially the filters in the water separators in the air-conditioning system, among others.
Just another day at the office.