How can I make my old dad's mobility scooter faster so he can keep up when we go for a drive in the country

I assume it has a battery powered electric motor. If where you vacation is mostly flat ground you can do either of two things: #1. Install a larger sprocket on the motor by one or two teeth. Measure the motor shaft with a vernier caliper to find out if it's metric or standard. Go to any bearing company in your area as they can get any size: # of teeth, shaft and pitch (Distance between teeth).
#2. Install a larger rear tire circumference. If you want to get fancy a slightly larger diameter wheel rim / tire combination.

It's important to do one or the other of these ideas. If you try to do both the poor little electric motor may not have enough power for the higher gear ratio.
Another thing. Most of these little carts are made in China and everything will be metric.

Tow rope.

get a tow bar and hook him on to that !!

Fit a lawnmower engine, Briggs and Stratton or Tecumseh are best !!!!

Nitros oxide injection canister on ALL wheels.
Get him a crash helmut though.

Put it in front of your vehicle and push it along.

Ask NASA if they have any old rocket boosters they no longer need. Tell him to watch out for sheep though.

Fit it with a turbo engine Elric and watch it shoot up the road like a bat out of hell!!

Hi Elric, tie it onto the roof rack, my Father loved that,- feeling the soft wind blowing through his hair........ funny, but his hair never lay flat ,he always looked like he had a fright,lol.Love Jo xx

how fast do you want it go ?????

tie it to the back of the car Elric, he can hold on like he's water skiing! pmsl

Why don`t you just take him in the car when you go for a drive
in the country.Problem solved.You could tie him onto the
roof if space is an issue.

Trust you to ask a question like this elric. Dunno the answer though hun x

Twin Cab Webers or trade in for the GT Ferrari version.