Narrative:

Return flight to us using high frequency radio. Filed FL430. Cleared to climb and maintain FL430. Entire flight was uneventful. The following day when reviewing the flight I noticed an maa of FL410 along the route I had flown (ar-8). ATC cleared us at FL430 so I assumed they waived the maa of FL410, however paperwork now is much easier than later! I assumed that the maa is applicable only when using the elg VOR, but I am researching that. (I have also called the local FSDO for clarification.) considering all of the above, is near meaningless anyway. There were thunderstorms along the route to 39500-40000', so I would have requested FL430 even if I had seen the maa limit. If an aircraft under ATC control is cleared for an action doesn't the responsibility then fall on ATC? To prevent recurrence: it is now a requirement for company pilots to make sure that not only are MEA's, MCA's, etc adhered to but maa's also. It is so rare to think about a maximum altitude. You are usually more concerned with the minimum. Contributing factors: aircraft certified to FL510, stronger headwinds at lower altitude, decreased fuel flow at higher altitude, all leads to selecting high altitudes. Vlfirst officermega allows direct to any point so when flying domestically we are rarely on a route. Also: failure to properly study charts! Callback conversation with reporter revealed the following: reporter and I pretty much agreed that maa (maximum authority altitude) are most likely placed on some arwy segments because flts above those altitudes may have radio signals, which determine the arwy, interfered with by some other distant NAVAID or radio station. We also agreed that if he was navigating with long range navigation system such as omega this maa restriction would not apply to his flight along ar-8. We agreed that if we could get anymore positive information reference maa on charts we should try to disseminate the information as most pilots and controllers are not familiar with the restrictions. I pointed out many more arwy segments in the avp, hnk, ipt areas where jet arwys have maa shown. Reporter suggests that we publish any concrete information in our callback.

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Original NASA ASRS Text

Title: AFTER FLT, CORP PLT DISCOVERED HE HAD BEEN CLEARED AND FLOWN ABOVE THE MAXIMUM AUTH ALT (MAA) ON SEGMENT OF AR-8 AIRWAY. NOT SURE IF LEGAL OR NOT.

Narrative: RETURN FLT TO U.S. USING HIGH FREQ RADIO. FILED FL430. CLRED TO CLB AND MAINTAIN FL430. ENTIRE FLT WAS UNEVENTFUL. THE FOLLOWING DAY WHEN REVIEWING THE FLT I NOTICED AN MAA OF FL410 ALONG THE ROUTE I HAD FLOWN (AR-8). ATC CLRED US AT FL430 SO I ASSUMED THEY WAIVED THE MAA OF FL410, HOWEVER PAPERWORK NOW IS MUCH EASIER THAN LATER! I ASSUMED THAT THE MAA IS APPLICABLE ONLY WHEN USING THE ELG VOR, BUT I AM RESEARCHING THAT. (I HAVE ALSO CALLED THE LCL FSDO FOR CLARIFICATION.) CONSIDERING ALL OF THE ABOVE, IS NEAR MEANINGLESS ANYWAY. THERE WERE TSTMS ALONG THE ROUTE TO 39500-40000', SO I WOULD HAVE REQUESTED FL430 EVEN IF I HAD SEEN THE MAA LIMIT. IF AN ACFT UNDER ATC CTL IS CLRED FOR AN ACTION DOESN'T THE RESPONSIBILITY THEN FALL ON ATC? TO PREVENT RECURRENCE: IT IS NOW A REQUIREMENT FOR COMPANY PLTS TO MAKE SURE THAT NOT ONLY ARE MEA'S, MCA'S, ETC ADHERED TO BUT MAA'S ALSO. IT IS SO RARE TO THINK ABOUT A MAX ALT. YOU ARE USUALLY MORE CONCERNED WITH THE MINIMUM. CONTRIBUTING FACTORS: ACFT CERTIFIED TO FL510, STRONGER HEADWINDS AT LOWER ALT, DECREASED FUEL FLOW AT HIGHER ALT, ALL LEADS TO SELECTING HIGH ALTS. VLF/OMEGA ALLOWS DIRECT TO ANY POINT SO WHEN FLYING DOMESTICALLY WE ARE RARELY ON A ROUTE. ALSO: FAILURE TO PROPERLY STUDY CHARTS! CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR AND I PRETTY MUCH AGREED THAT MAA (MAX AUTHORITY ALT) ARE MOST LIKELY PLACED ON SOME ARWY SEGMENTS BECAUSE FLTS ABOVE THOSE ALTS MAY HAVE RADIO SIGNALS, WHICH DETERMINE THE ARWY, INTERFERED WITH BY SOME OTHER DISTANT NAVAID OR RADIO STATION. WE ALSO AGREED THAT IF HE WAS NAVIGATING WITH LONG RANGE NAV SYS SUCH AS OMEGA THIS MAA RESTRICTION WOULD NOT APPLY TO HIS FLT ALONG AR-8. WE AGREED THAT IF WE COULD GET ANYMORE POSITIVE INFO REF MAA ON CHARTS WE SHOULD TRY TO DISSEMINATE THE INFO AS MOST PLTS AND CTLRS ARE NOT FAMILIAR WITH THE RESTRICTIONS. I POINTED OUT MANY MORE ARWY SEGMENTS IN THE AVP, HNK, IPT AREAS WHERE JET ARWYS HAVE MAA SHOWN. RPTR SUGGESTS THAT WE PUBLISH ANY CONCRETE INFO IN OUR CALLBACK.

Data retrieved from NASA's ASRS site as of August 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.