To the frequent flyer, the various sights, smells and noises encountered on an aircraft are barely noticed.
For the person who only flies occasionally, or most especially anyone who's afraid of flying, these can be perplexing at best and downright terrifying at worst. I thought that by giving you an idea of what may be encountered after you've taken your seat, it might help to alleviate your fears a bit. In fact, if you watch and listen for these sights and noises, it should take your mind off the fear you may be feeling.
Like any machine, every aircraft makes a unique sound. When the aeroplane's doors have been shut, probably the first thing you'll notice is the brief 'pushback' as the tractor towing the aircraft pushes it onto the runway. You may hear the tractor's engine too. While the tractor's busy doing its pushing, the aircraft's engines will start.
Immediately prior to them starting, the air conditioning will be turned off. The reason for this is that the airflow is required to turn the turbines. Once the engines have started, back will come the air conditioning.
The aircraft will then start to taxi to the runway. This can be a bit of a bumpy ride, I'm afraid! During this period, the pilots start their pre-flight checks, so you may feel the brakes being applied a couple of times. No, you're not about to crash. They're just testing them.
Also at this time, you'll notice various parts of the wings move up and down. No, bits are not flying off the wings. These are known as ailerons, spoilers and flaps.
Since the engines are running, and the plane's moving, you may be under the impression that the aircraft's at full power. It is not. First, the aircraft will line up on the runway, and then the throttles will be advanced to take-off power. This is quite a noise, so try not to be alarmed. Also, you may feel the aircraft jump forward a little as the brakes are released.
When the plane actually starts to move and make its take-off run, you'll probably feel little bumps, like a car going over cats-eyes in the road. In fact, this is rather what's happening. There are lights that illuminate the runway center-line, and the nose wheel is lined up to go over these.
Shortly after the aircraft has actually taken off, the wheels will be raised back into the aircraft. Since they're activated by hydraulics, you may hear a couple of 'clunks' as the hydraulic pressure is applied and removed.
Soon after the aircraft's taken off, during the period when it's still climbing, the nose may be lowered and you may hear a drop in engine noise. This is to comply with any noise abatement code that may be in place.
The last thing you'll see and hear will be the sound of the flaps retracting back into the wings. I assure you they're not bits flying off. The flaps are used to help the plane during take-off.
I hope this little explanation will help allay your fears to some extent