Narrative:

On flight from phx to phl during a descent on the bunts 1 arrival to phl, I received a clearance to FL240 by ZNY. The PNF (first officer) was off the #1 radio gathering ATIS information and contacting company at phl on the #2 radio. During this time, ZNY handed me off to the next sector. The previous sector had given us a heading for flow control. This new sector's clearance read something like this: 'air carrier X, cleared direct har, cleared to FL250 by 40 mi west of har, maintain 300 KTS.' this clearance did not appear to negate our previous clearance to FL240. To be certain, I asked the controller to repeat this clearance. This request for a repeat of the clearance did not seem to go well with this controller who promptly blurted out what sounded like the same exact thing he said the first time, equally as fast. I read it back and continued my descent to FL240. This controller queried my present altitude of FL240 and said that I was to be at FL250. I reminded him of our previous clearance to FL240 and that his clearance to FL250 by 40 mi of har did not negate my clearance to FL240. His clearance did not indicate a mandatory altitude, but rather an altitude to be 'by' before 40 mi west of har. He then stated he had given me this clearance 3 times. The clearance was given only twice, and the second time at my request based on the discrepancy of the previous clearance altitude. I then assertively repeated the issue of being at FL250 40 mi west of har as opposed to cleared to FL250 by 40 mi west of har. I then reminded him we were at FL240, what did he want us to do now. His tone changed and he was much calmer now, and responded to maintain FL240 and contact new york on (next sector). There are controllers out there who do not realize that not all radio xmissions are created equal. Some are very clear and very crisp (loud and clear). Some have static in the backgnd, whereas others have conversations in the backgnd making it difficult to the receiving end. Some are muffled while others sound almost mute, and you struggle to hear. And some have distinguishable voices while others are barely clear. So when a controller rapidly blurts out several numbers in one clearance (sentence) with any of the above mentioned transmission difficulties, he is inviting confusion. There also needs to be standardization on arrs for altitude constraints at designated fixes. Over 90% of ctrs adhere to the published constraints. The others, such as ZNY, are never consistent and sometimes more than 1 per arrival is common. Our A320's and 319's software for non-stored waypoints are not user friendly for this, whereas the boeing FMC has quick and easy software to place in a point between present position and the next fix. Time and altitude constraints for the longer process on the airbus can confuse the profile information often forcing us to use manual operation of profile rather than using the modern technology on a very technological aircraft. The STAR arrival is one of the most critical phases of flight. Not only can the other pilot be on a different radio, the ATIS information programmed into the computer can throw out all previously programmed constraints if a different runway is accessed during this time, per ATIS information, making profiles for descent even further difficult to maintain. If controllers understood this better, they might issue less numbers in a single clearance, be more attentive to previous clrncs, thus exercising caution when changing altitudes on a descent from a lower altitude to a higher altitude, realizing that words as simple as 'by' and 'at' can change an entire clearance.

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Original NASA ASRS Text

Title: ZNY ARTCC CTLR USES NON STANDARD PHRASEOLOGY RESULTING IN AN EXCURSION FROM ASSIGNED ALT.

Narrative: ON FLT FROM PHX TO PHL DURING A DSCNT ON THE BUNTS 1 ARR TO PHL, I RECEIVED A CLRNC TO FL240 BY ZNY. THE PNF (FO) WAS OFF THE #1 RADIO GATHERING ATIS INFO AND CONTACTING COMPANY AT PHL ON THE #2 RADIO. DURING THIS TIME, ZNY HANDED ME OFF TO THE NEXT SECTOR. THE PREVIOUS SECTOR HAD GIVEN US A HDG FOR FLOW CTL. THIS NEW SECTOR'S CLRNC READ SOMETHING LIKE THIS: 'ACR X, CLRED DIRECT HAR, CLRED TO FL250 BY 40 MI W OF HAR, MAINTAIN 300 KTS.' THIS CLRNC DID NOT APPEAR TO NEGATE OUR PREVIOUS CLRNC TO FL240. TO BE CERTAIN, I ASKED THE CTLR TO REPEAT THIS CLRNC. THIS REQUEST FOR A REPEAT OF THE CLRNC DID NOT SEEM TO GO WELL WITH THIS CTLR WHO PROMPTLY BLURTED OUT WHAT SOUNDED LIKE THE SAME EXACT THING HE SAID THE FIRST TIME, EQUALLY AS FAST. I READ IT BACK AND CONTINUED MY DSCNT TO FL240. THIS CTLR QUERIED MY PRESENT ALT OF FL240 AND SAID THAT I WAS TO BE AT FL250. I REMINDED HIM OF OUR PREVIOUS CLRNC TO FL240 AND THAT HIS CLRNC TO FL250 BY 40 MI OF HAR DID NOT NEGATE MY CLRNC TO FL240. HIS CLRNC DID NOT INDICATE A MANDATORY ALT, BUT RATHER AN ALT TO BE 'BY' BEFORE 40 MI W OF HAR. HE THEN STATED HE HAD GIVEN ME THIS CLRNC 3 TIMES. THE CLRNC WAS GIVEN ONLY TWICE, AND THE SECOND TIME AT MY REQUEST BASED ON THE DISCREPANCY OF THE PREVIOUS CLRNC ALT. I THEN ASSERTIVELY REPEATED THE ISSUE OF BEING AT FL250 40 MI W OF HAR AS OPPOSED TO CLRED TO FL250 BY 40 MI W OF HAR. I THEN REMINDED HIM WE WERE AT FL240, WHAT DID HE WANT US TO DO NOW. HIS TONE CHANGED AND HE WAS MUCH CALMER NOW, AND RESPONDED TO MAINTAIN FL240 AND CONTACT NEW YORK ON (NEXT SECTOR). THERE ARE CTLRS OUT THERE WHO DO NOT REALIZE THAT NOT ALL RADIO XMISSIONS ARE CREATED EQUAL. SOME ARE VERY CLR AND VERY CRISP (LOUD AND CLR). SOME HAVE STATIC IN THE BACKGND, WHEREAS OTHERS HAVE CONVERSATIONS IN THE BACKGND MAKING IT DIFFICULT TO THE RECEIVING END. SOME ARE MUFFLED WHILE OTHERS SOUND ALMOST MUTE, AND YOU STRUGGLE TO HEAR. AND SOME HAVE DISTINGUISHABLE VOICES WHILE OTHERS ARE BARELY CLR. SO WHEN A CTLR RAPIDLY BLURTS OUT SEVERAL NUMBERS IN ONE CLRNC (SENTENCE) WITH ANY OF THE ABOVE MENTIONED XMISSION DIFFICULTIES, HE IS INVITING CONFUSION. THERE ALSO NEEDS TO BE STANDARDIZATION ON ARRS FOR ALT CONSTRAINTS AT DESIGNATED FIXES. OVER 90% OF CTRS ADHERE TO THE PUBLISHED CONSTRAINTS. THE OTHERS, SUCH AS ZNY, ARE NEVER CONSISTENT AND SOMETIMES MORE THAN 1 PER ARR IS COMMON. OUR A320'S AND 319'S SOFTWARE FOR NON-STORED WAYPOINTS ARE NOT USER FRIENDLY FOR THIS, WHEREAS THE BOEING FMC HAS QUICK AND EASY SOFTWARE TO PLACE IN A POINT BTWN PRESENT POS AND THE NEXT FIX. TIME AND ALT CONSTRAINTS FOR THE LONGER PROCESS ON THE AIRBUS CAN CONFUSE THE PROFILE INFO OFTEN FORCING US TO USE MANUAL OP OF PROFILE RATHER THAN USING THE MODERN TECHNOLOGY ON A VERY TECHNOLOGICAL ACFT. THE STAR ARR IS ONE OF THE MOST CRITICAL PHASES OF FLT. NOT ONLY CAN THE OTHER PLT BE ON A DIFFERENT RADIO, THE ATIS INFO PROGRAMMED INTO THE COMPUTER CAN THROW OUT ALL PREVIOUSLY PROGRAMMED CONSTRAINTS IF A DIFFERENT RWY IS ACCESSED DURING THIS TIME, PER ATIS INFO, MAKING PROFILES FOR DSCNT EVEN FURTHER DIFFICULT TO MAINTAIN. IF CTLRS UNDERSTOOD THIS BETTER, THEY MIGHT ISSUE LESS NUMBERS IN A SINGLE CLRNC, BE MORE ATTENTIVE TO PREVIOUS CLRNCS, THUS EXERCISING CAUTION WHEN CHANGING ALTS ON A DSCNT FROM A LOWER ALT TO A HIGHER ALT, REALIZING THAT WORDS AS SIMPLE AS 'BY' AND 'AT' CAN CHANGE AN ENTIRE CLRNC.

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.