The planes will be flying at speeds of 70-80 miles an hour, possibly up to 100 mph.
The aircraft will only be two metres apart wingtip to wingtip and flying just 30 feet off the ground as they make their passes over the airstrip.
The two girls have been given instructions on how to signal to the pilots: Thumbs up and a big scream means they're enjoying themselves. Thumbs down if they want to stop.
And if the girls are feeling very comfortable they're hoping to attempt a 'superwoman' pose as well.
Rose Powell and Flame Brewer, both nine-years-old, have become the youngest in the world to perform wingwalking stunts in formation.
Rose Powell and Flame Brewer have become the youngest in the world to perform a daredevil stunt in formation when they took to the skies over Gloucestershire on Wednesday morning.
Two nine year old girls will follow in the footsteps of our weatherman Alex Beresford when they go wing walking on Wednesday.
Rose Powell and Flame Brewer will become the youngest in the world to perform the daredevil stunt in formation when they take to the skies over Gloucestershire.