Date: 201204
Local time of day: 1201-1800
Location: DCA.Airport, DC
Flight conditions: VMC
Light: Daylight
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class B DCA
ATC / advisory: TRACON PCT
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown
Second reporter function: Pilot Flying; First Officer
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Airspace Violation All Types
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Took Evasive Action
Contributing factors: Procedure; Human Factors; ATC Equipment / Nav Facility / Buildings; Aircraft
Primary problem: Ambiguous

Narrative: A loss of communications occurred with ATC while on a vectored arrival to DCA which allegedly resulted in a transgression of P56 airspace. The flight was being operated without capability of RNAV navigation. Due to the navigation limitations we were unable to fly the CLIPR ONE RNAV ARRIVAL. I queried Potomac Approach about this prior to reaching BAL VOR and in lieu of the RNAV arrival Potomac Approach assigned us a clearance to fly direct to DCA VOR after BAL VOR. I again questioned this clearance limit as it put P56 between our position and our clearance limit fix; and Potomac said to expect a vector. At some point while flying direct from BAL to DCA I became suspect of our position in relation to where we typically would have received a vector to enter the downwind for Runway 1 and avoid P56. I asked ATC if they 'had a turn' for us and received no reply. I then asked several more times for ATC instruction and received no reply; then other aircraft began to answer me and I heard an attempt to contact us on my number two comm which was tuned to 121.5. At this point both the Approach frequency and 121.5 were being 'stepped on' so severely that communication was lost. All the while we were continuing to encroach on the P56 area with no directive from ATC. The fact that if we maintained our present heading we would fly through P56 became obvious to the First Officer and myself. At this point the First Officer initiated a turn to the east to avoid P56 while I continued to try to establish communication with ATC. ATC eventually figured out their radio was bad and assigned all aircraft to a new frequency. While in our turn to avoid P56 the First Officer and I noted how close we had come to the P56 depicted area; but did not believe that we had breached the airspace at that point as there is no easily definable point to identify P56 airspace from the air on the northeast side. After arriving at the gate safely; I asked Ground Control for the Potomac Approach Control number. The Ground Controller gave me the phone number and asked me if there was a problem. I responded that I simply had a question and he made a reference that 'everything was OK.' I then proceeded to call Potomac and the initial person I spoke with also indicated that the occurrence was induce by a comm failure on their end and that everything was 'ok'. Then the person said to wait a minute while he spoke to someone else an then informed me that I went through a corner of P56 and that an investigation was to follow; he then took my name; address and certificate number. The event occurred because of a communications failure with ATC at the most critical time on an arrival that required precise vectoring in order to avoid P56 airspace. Once the comfort level with the proximity to P56 deteriorated my First Officer who was the flying pilot initiated a turn without ATC command to avoid P56. All these events occurred in a very short time frame. Its obvious that P56 is to be avoided; but on a vectored approach in close proximity to the airport and a loss of communications there is no clear avoidance procedure or directive as what to do or how to exactly define P56. Perhaps a simple visual arrival from the north east that provides guidance as where to turn in the event of lost comm. Perhaps 'stay east of the Anacostia River and proceed to enter downwind'.


Second narrative: Our day started with an MEL'd FMS. This MEL prevented us from flying any RNAV procedures. While en route to DCA we were cleared 'after Baltimore; direct to the DCA VOR. Expect vectors for the Mount Vernon Visual to Runway 1.' All other RNAV capable aircraft were on the CLIPR 1 arrival. Some time after crossing BAL we noticed that we could only hear other aircraft transmitting but no response from Potomac Approach. At this point we were flying our last assigned route/clearance; direct to DCA VOR to expect vectors. The other aircraft confirmed they had the same problem as we did. We could all hear each other but no one could hear Potomac Approach. The Captain was actively trying to re establish communication with approach. I as the pilot flying was suspicious that we may be getting close to P-56; this is when I commenced a left hand turn with out ATC instruction. Very shortly there after Potomac Approach re established communication and advised all aircraft to contact them on a new frequency. We were then vectored for the Mount Vernon Visual to Runway 1 approach; with a circle to land 33. The contributing factors were as follows. First and foremost was the loss of radio communication with Potomac Approach. Had this not occurred we would have received the expected vector to join the downwind. Second; the MEL'd FMS. Had the FMS been operational we would have been able to fly the CLIPR 1 RNAV arrival with the built in left turn at BRUNC.


Synopsis: Air Carrier flight crew reports possible P56 incursion when lost communication with PCT occurs after being cleared from BAL direct to DCA and expect vectors. The flight had been dispatched with the FMC MEL'd.