Narrative:

We were assigned the whitestone climb off runway 13 in lga. During taxi-out; short of the runway; we were assigned the coney climb. According to the LGA1 departure; the coney/maspeth climbs require a climb gradient of 900 ft per NM to 1500 ft. Since we accelerate at 1000 ft to 200 KIAS; this would require a climb rate of 3000 ft. We did not have a chart on the flight deck showing how fast we can climb based on weight/temperature; and based on previous discussions with dispatch and the program mgrs; they do not have the data either. The maspeth climb appears to be more critical; with the 5000 ft required altitude passing the 220 degree lga radial. We told tower we could not comply with the climb gradient and were cleared via the coney climb with no climb gradient requirement. We observed a climb rate of 1700 FPM in the climb to 1500 ft (wing/cowl anti-ice in use). My question is; can we fly these climbs without the data? Should they be unauthorized similar to runway 32 in bos? How many crews are accepting these climbs without realizing they don't have the required performance? How can I ensure compliance with any climb procedure requiring a climb gradient; especially on a hot summer day?

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Original NASA ASRS Text

Title: FO WONDERS IF HIS COMPANY'S STANDARD CLIMB PROCEDURES PROVIDE ADEQUATE PERFORMANCE TO MEET SPECIFIED CLIMB GRADIENTS ON SIDS.

Narrative: WE WERE ASSIGNED THE WHITESTONE CLB OFF RWY 13 IN LGA. DURING TAXI-OUT; SHORT OF THE RWY; WE WERE ASSIGNED THE CONEY CLB. ACCORDING TO THE LGA1 DEP; THE CONEY/MASPETH CLBS REQUIRE A CLB GRADIENT OF 900 FT PER NM TO 1500 FT. SINCE WE ACCELERATE AT 1000 FT TO 200 KIAS; THIS WOULD REQUIRE A CLB RATE OF 3000 FT. WE DID NOT HAVE A CHART ON THE FLT DECK SHOWING HOW FAST WE CAN CLB BASED ON WT/TEMP; AND BASED ON PREVIOUS DISCUSSIONS WITH DISPATCH AND THE PROGRAM MGRS; THEY DO NOT HAVE THE DATA EITHER. THE MASPETH CLB APPEARS TO BE MORE CRITICAL; WITH THE 5000 FT REQUIRED ALT PASSING THE 220 DEG LGA RADIAL. WE TOLD TWR WE COULD NOT COMPLY WITH THE CLB GRADIENT AND WERE CLRED VIA THE CONEY CLB WITH NO CLB GRADIENT REQUIREMENT. WE OBSERVED A CLB RATE OF 1700 FPM IN THE CLB TO 1500 FT (WING/COWL ANTI-ICE IN USE). MY QUESTION IS; CAN WE FLY THESE CLBS WITHOUT THE DATA? SHOULD THEY BE UNAUTH SIMILAR TO RWY 32 IN BOS? HOW MANY CREWS ARE ACCEPTING THESE CLBS WITHOUT REALIZING THEY DON'T HAVE THE REQUIRED PERFORMANCE? HOW CAN I ENSURE COMPLIANCE WITH ANY CLB PROC REQUIRING A CLB GRADIENT; ESPECIALLY ON A HOT SUMMER DAY?

Data retrieved from NASA's ASRS site as of May 2009 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.