Has any got any experience with taking a cat in an airplane. Do they freak
out from the loud noise. Do they have problems with the change in altitude?

I've had a cat in the plane. It wasn't fun.

After a long day of flying, hanging out, eating burgers, and generally
having fun, it was time to depart for home. But as often happens on a
beautiful warm evening, I didn't get around to going until after dark.
I had flown the plane several times that day with no issues, so a
walkaround with a flashlight quickly convinced me that there were no
issues that would prevent me from making the 15 minute flight home.

I got in, strapped in, started up, did a quick runup and pulled out
onto the runway. The runway was grass with no markings, but it did
have lights. Off the end of the runway there were only open fields,
so there was something of a black hole effect, but the plane had a
full gyro panel and I was prepared for this.

I was not prepared for what happened at rotation. There was a sharp
pain in my left shoulder, and then a big fat fuzzy thing climbed into
my lap, completely blocking my view of the instrument panel. It was a
cat from one of the hangar homes.

I generally like cats, and really don't mind them climbing on my lap
to be petted under normal circumstances, but this was a little much.
Keeping one hand on the yoke, I used the other to try and shoo the cat
away. I didn't dare lower the nose - there were power lines that I
had to clear - so I stared off into the darkness trying to discern a
horizon. There were a few lights in the distance, and by holding
those in position relative to the bracing tubes in the cockpit, I
maintained some semblance of a wings-level climb attitude.

The cat, now throughly miffed, climbed off my lap and onto the dash.
This was an improvement of sorts - I could now see the instruments -
but a big chunk of my view forward was blocked and that would not do
for landing. The cat curled up in the corner of the windshield to
sulk.

More prodding got the feline to move, and as she tried to cross to the
other side of the dash, I grabbed the furball and threw her into the
back seat. All this took about a minute, I think, since I was now at
about 600 ft. I turned crosswind, flew a pattern, and landed without
further incident to an accompaniment of annoyed meowing from the back.
I then reached into the back, opened the rear door, and the stowaway
made her escape.

My second attempt at returning home was uneventful.

Michael