As stated by the Wanderer
As long as you are on ground, you might have a look at the groundspeed indication that comes from the IRS.
That schould give a rough estimate, with the reported wind of 020/10kt close enough.
First of all... good job by the crew for protecting life and limb
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Let's not forget the Stanby Airspeed Indicator. Saved my bacon on a steam driven aircraft about 10 years ago. We were also lucky because VMC conditions prevailed.