A crew reported that after departing on the las boach four RNAV they failed to climb to the witla 10...

Attributes
ACN	973920
Time
Date	201110
Local Time Of Day	1201-1800
Place
Locale Reference	L30.TRACON
State Reference	NV
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Light Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 135
Flight Phase	Climb
Route In Use	SID BOACH FOUR RNAV
Flight Plan	IFR
Component
Aircraft Component	FMS/FMC
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Deviation - Altitude Crossing Restriction Not Met Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy

Narrative:

We were assigned to do the boach four RNAV departure out of las. We departed off of runway 1L. We were told by departure to climb via the boach four RNAV departure. We started complying with the departure crossing bessy at 230 KTS. Next restriction was at witla. It reads at or below 10;000 (ATC) and at or above 7;900. I read that to mean that ATC assigns the 10;000 and if not assigned by them; we were to climb at or above 7;900 ft; which is what we were doing. We decided to ask for clarification; unfortunately too late. When we called; they proceeded to tell us we did not comply with climb altitude. We asked them if they wanted us to descend back down and they told us no. We continued to fly the departure with no further complications. Remove the (ATC) off of the restriction.

Original NASA ASRS Text

Title: A Crew reported that after departing on the LAS BOACH FOUR RNAV they failed to climb to the WITLA 10;000 FT ATC crossing restriction because they did not understand the charted constraint.

Narrative: We were assigned to do the Boach Four RNAV Departure out of LAS. We departed off of runway 1L. We were told by departure to climb via the Boach Four RNAV Departure. We started complying with the departure crossing Bessy at 230 KTS. Next restriction was at WITLA. It reads at or below 10;000 (ATC) and at or above 7;900. I read that to mean that ATC assigns the 10;000 and if not assigned by them; we were to climb at or above 7;900 FT; which is what we were doing. We decided to ask for clarification; unfortunately too late. When we called; they proceeded to tell us we did not comply with climb altitude. We asked them if they wanted us to descend back down and they told us no. We continued to fly the departure with no further complications. Remove the (ATC) off of the restriction.

Data retrieved from NASA's ASRS site as of April 2012 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.

A crew reported that after departing on the las boach four RNAV they failed to climb to the witla 10;000 ft ATC crossing restriction because they did not understand the charted constraint.