No official, officer, or employee compensated with state funds shall be reimbursed for airplane travel in an amount in excess of standard coach fare for the applicable flight. Unless an emergency situation arises and the purchase or reimbursement for the purchase of tickets for travel by air in excess of the standard coach fare for such emergency situation is approved by the comptroller, no state funds shall be otherwise used to purchase air travel at rates in excess of standard coach fare for the applicable flight.