Narrative:

While in cruise flight heard a 'pop' and subsequently lost engine manifold pressure and cabin pressurization. Contacted controller and stated that I needed to get to the closest airport because I had suffered a severe drop in manifold pressure. Also said that I had 1 soul and 70 gallons fuel on board. Controller then told me to descend to 3000 to which I replied that I would be remaining at a higher altitude until directly over the airport. I was then handed off to dulles approach and again told to descend to 3000 which was followed by a repeat of my intentions. The controller then said 'aren't you landing at martinsburg?' I said, 'ok, to eliminate any confusion, I am declaring an emergency and will maintain a slow climb until over mrb -- let's roll the equipment at martinsburg.' the controller then handed me off to another dulles sector. This controller also told me to descend, to which I refused. The controller said 'do you have a problem?' I told her that I had declared an emergency with the previous controller to which she replied, 'I'm sorry sir, that information wasn't passed along to me.' a safe landing followed and an investigation revealed a loose hose in the turbo charging system. An unofficial source told me that the controllers didn't know what 'loss of manifold pressure' meant and assumed that I had just lost cabin pressurization. Regardless, the controllers were not relaying the information that I had given them, not understanding what manifold pressure is, is not excuse.

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Original NASA ASRS Text

Title: CORPORATE ACFT HAS MANIFOLD PRESSURE PROBLEM AND REQUESTS LAND NEAREST ARPT. STATES HE WISHES TO REMAIN HIGH UNTIL OVER THE ARPT. INFO NOT PASSED TO NEXT CTLR WHO REQUESTS DSCNT. DECLARES EMER. STILL REQUESTED TO DSND.

Narrative: WHILE IN CRUISE FLT HEARD A 'POP' AND SUBSEQUENTLY LOST ENG MANIFOLD PRESSURE AND CABIN PRESSURIZATION. CONTACTED CTLR AND STATED THAT I NEEDED TO GET TO THE CLOSEST ARPT BECAUSE I HAD SUFFERED A SEVERE DROP IN MANIFOLD PRESSURE. ALSO SAID THAT I HAD 1 SOUL AND 70 GALLONS FUEL ON BOARD. CTLR THEN TOLD ME TO DSND TO 3000 TO WHICH I REPLIED THAT I WOULD BE REMAINING AT A HIGHER ALT UNTIL DIRECTLY OVER THE ARPT. I WAS THEN HANDED OFF TO DULLES APCH AND AGAIN TOLD TO DSND TO 3000 WHICH WAS FOLLOWED BY A REPEAT OF MY INTENTIONS. THE CTLR THEN SAID 'AREN'T YOU LNDG AT MARTINSBURG?' I SAID, 'OK, TO ELIMINATE ANY CONFUSION, I AM DECLARING AN EMER AND WILL MAINTAIN A SLOW CLB UNTIL OVER MRB -- LET'S ROLL THE EQUIP AT MARTINSBURG.' THE CTLR THEN HANDED ME OFF TO ANOTHER DULLES SECTOR. THIS CTLR ALSO TOLD ME TO DSND, TO WHICH I REFUSED. THE CTLR SAID 'DO YOU HAVE A PROBLEM?' I TOLD HER THAT I HAD DECLARED AN EMER WITH THE PREVIOUS CTLR TO WHICH SHE REPLIED, 'I'M SORRY SIR, THAT INFO WASN'T PASSED ALONG TO ME.' A SAFE LNDG FOLLOWED AND AN INVESTIGATION REVEALED A LOOSE HOSE IN THE TURBO CHARGING SYS. AN UNOFFICIAL SOURCE TOLD ME THAT THE CTLRS DIDN'T KNOW WHAT 'LOSS OF MANIFOLD PRESSURE' MEANT AND ASSUMED THAT I HAD JUST LOST CABIN PRESSURIZATION. REGARDLESS, THE CTLRS WERE NOT RELAYING THE INFO THAT I HAD GIVEN THEM, NOT UNDERSTANDING WHAT MANIFOLD PRESSURE IS, IS NOT EXCUSE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.