Most of the District is a no-fly zone, with the exception of military aircraft, right? So how do hospital-to-hospital emergency transport helicopters fit in? They must have to fly over the Mall and major federal buildings all the time. Do they have to take a circuitous route to miss those buildings? Are they a potential terrorist threat?

Relax. When you’re hemorrhaging blood and need transport from one hospital to another, your helicopter will be able to fly over the Mall, across the Ellipse, or above any other area within the District’s 15-square-mile restricted flight zone—as long as the hospital or charter company that owns the helicopter has applied for the proper waiver.

“Security is our key mission, but we realize that life-threatening situations are also an important consideration,” says Transportation Security Administration spokesperson Amy Kudla.

The waivers come in two forms—advance and emergency. To get advance clearance, companies apply for a Federal Aviation Administration (FAA) waiver, which is then vetted by the Transportation Security Administration (TSA). Based on the National Capitol Region Air Space Control’s assessments of the current intelligence, the District’s threat level and a handful of other considerations, the FAA approves or disapproves the waiver within seven days. When a helicopter needs to dispatch, the pilot registers his or her name, tail number, and exact flight plan with the TSA along with the pre-approved waiver number.

For emergency clearance, helicopters must be equipped with a two-way radio and maintain two-way radio communications at all times; the helicopter must be equipped with an operating transponder, obtain a specific transponder code from air traffic control and continuously transmit it; the pilot must file instrument flight rules and visual flight rules prior to departure or prior to entering the District; and the aircraft operator also register their name, tail number, and flight plan with the TSA.

And when helicopters veer from their flight plans, TSA responds instantly to curtail any threat, Kudla says.

Every Monday, the ‘Huh?’ Bub takes your questions. Got one?