The 89th airlift squadron (AKA VIP taxi) has a finite number of aircraft of each type. They can only allocate assets according to what they have. The G-III and G-V aircraft are probably the easiest to assign to the Speaker of the House, and probably most suited to the mission.


They aircraft used to fly the President and the Vice President are specialized aircraft, with full military communications suites (read $$$$$$$$$) onboard so the President or if necessary the Vice President can carry out command functions regardless of where they are. If Madame Speaker wishes to appropriate that type of aircraft for her use, she most certainly may. Those aircraft, however, are not assembled overnight. I just don't see the need for it, as it is highly unlikely for overall Command to fall on the Speaker's shoulders without warning short of a nuclear strike.

Should the Speaker have an aircraft available? Yes, as it would ease the Secret Service's burden. I just don't see what the big deal is about stopping to refuel, as there are USAF bases scattered all across the country. She wouldn't even have to worry about landing at a commercial airport.