First Which speed?
We fly an aircraft relatively to the Air in IAS (Indicated Airspeed) but this IAS has to be corrected to become a TAS and TAS is greater than IAS, then we have to add the wind.
So if we are in circumstances with a low air density and some downwind our ground speed is high compared to the IAS, but the pilot has to fly IAS.
Secondly: Human Performances
Everybody knows the superficiality of human feelings and we spend hours studying "Human Performances and Limitations" in our training, personnally when I am a PAX I am distrustful about what I feel when in the Cabin, because I cannot read the instruments which are the only believable source.
Make the experience in your car, try to estimate the speed without looking your speedometer, have you never overspeed a little without any will to do it? Personnally, I surprise myself last week as I was quietly driving in NE Thailand and trapped by a Police Radar (Yes police has a radar in Nakhon Phanom!!!), and I was really of good will, I was underestimating my speed by just looking outside. The inverse maybe true, it depends on my fatigue state.
Cheers
PS
It is a new Car (I do not want to be censored so I cannot give the model) with all the instruments centered on the Car axis (Between Driver and Passenger), and not as usually in front of the wheel.
Initially it sounds good as the wheel is not masking the instruments, but I found at several occasions that, with this lay out, we look less the instruments as they are not in front of you. You are obliged to look aside as it is not in your straight visual field.
It is not a natural lay out, and I noticed few times that I was mistaking on the situation,because relying more on feelings than instruments.
Last edited by ASIAN FROG; 13th Nov 2006 at 22:34.