Steve, your second para refers to the climb out so I presume the first paragraph refers to the acceleration on the ground through the take off roll and rotation until the wheels leave the ground. In this case the ASI will function perfectly normally throughout the take off ground roll if the static port is taped over. It is only when the aircraft starts to gain altitude that the ASI would start to misread as the static pressure within the instrument case would no longer be able to compensate for the ambient pressure reduction with gain of altitude.
Also, quote ‘therefore the air pressure coming in through the pitot won’t register the true air speed’ – The pressure sensed in the pitot is used to derive indicated airspeed on the ASI although I’m sure that’s what you meant to say.
There are also other implications to this accident in that the pressures sensed by the pitot and static ports (and there are several of each) are fed to the Air Data Computers which not only supply the instrumentation but also systems such as the Thrust Management Computer. Duff pressures would therefore command the autothrottle to set the wrong take-off thrust amongst other problems.
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