Many standardized tests, including the SAT, ACT, GRE and GMAT do allow the use of a calculator, and I believe the ASVAB should too. I posed this argument to the Department of Defense in October of 2011 and an aide to the Undersecretary of the US Navy wrote back stating that it was under consideration. As of today, Sept. 9, 2012, the change has not been made and paper and pencil are your only calculator.
I've been preparing students for this exam, with a very high rate of success, for many years and I've developed a "calculator sheet" that my students memorize and write on the scrap paper provided as soon as they sit down. It has all of the formulas you will need and other useful facts as well. In addition, I have developed a 4 week series of notebooks that each of my students receives so your preparation will be very strong and secure. In fact, many of the men and women I work with end up deciding to take their SAT/ACT exam at the same time so that they can expand their choice of college options.
I welcome your inquiry about ASVAB prep. and .....thank you, in advance, for defending our country.