Light Transport; Low Wing; 2 Turbojet Eng
Workload; Time Pressure; Distraction; Communication Breakdown; Confusion
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert; Flight Crew Took Evasive Action; Flight Crew Returned To Clearance; Flight Crew Became Reoriented
Human Factors; Procedure; Company Policy
The initial clearance given prior to departure; was to Climb Via EXTAN4 except maintain 10;000 feet. After departure we were climbing at 250 knots with a vertical speed of over 3;000 fpm. Between 9;000 feet and 10;000 feet; Denver Departure cleared us to climb via SID and maintain FL230. Pilot not flying (PNF) set FL230 in the altitude alerter and confirmed with Pilot Flying (PF) the set altitude. PF acknowledged the set altitude. (By setting FL230 the FMS dropped the 10;000 Feet limit) I then asked; 'Where do we need to be?' as the Captain was reaching to arm and activate the Vertical Navigation function of the flight director and at the same time reached to retrieve the Primary Electronic Flight Bag (EFB) which was stowed prior to departure. There was not enough time to open the primary EFB & retrieve directions for the departure prior to climbing through 10;000 feet. The Captain looked at the FMS screen and noticed the '10;000 At or Below' restriction for the KIDNG intersection just prior to our crossing it. At the same time our TCAS issued a traffic alert for an aircraft 2;300 feet above and to our 2:00 position. I disconnected the autopilot; manually stopped climb and began descent to 10;000 feet. Our flight had climbed to about 10;400 before descending. Denver Departure then stated that we should be at 10;000 and pointed out traffic above us at 2:00. After about ten seconds Denver issued a new clearance to climb unrestricted to FL230. The flight continued without further incident.There are several factors that lead to this situation. 1) We are required to stow our EFB's prior to departure which does not allow timely/immediate access if required; 2) ATC issued an altitude clearance immediately prior to approaching an altitude clearance limit indicating he required a climb; and 3) ATC regularly issues amended altitude clearances immediately prior to and approaching a clearance limit so as to not require an aircraft to leveled-off and immediately continue an altitude change. This conditions flight crews to often expect another altitude while approaching an altitude clearance limit.As I try to find a narrative that would outline suggestions for avoiding recurrence of this event I am having difficulty thinking of such a suggestion that is plausible and easy to incorporate. The only thing I can think is to memorize the departures and their corresponding altitudes and speeds. In this case; as we approached our clearance limit altitude of 10;000 feet we were focusing on leveling off. While the clearance of 'Climb Via Sid except maintain X Altitude' is given 99 percent of the time; the result is that a flight crew will disregard the SID altitudes and focus on the clearance altitude limit only. To be given a 'Climb Via Sid & Maintain FL230 within 1000 feet of a level off point' is; in my opinion; setting the flight crew up for failure.This entire incident took place in less than 30 seconds and could have been prevented if the departure controller had waited until we passed the KIDNG intersection before giving a subsequent 'Climb Via Sid' clearance. I am also quite certain that there was not sufficient time to even reference the SID chart if we had the Primary EFB open and turned on; not to mention that the FMS would not have had time to calculate the vertical navigation in the ten seconds it took to fly through our 10;000 feet altitude limit. Once the altitude alerter was set to FL230; as our training requires; the FMS dropped the altitude protection of 10;000 feet in this case. Also; the FMS often requires more than 30 seconds to compute the inputs and factor subsequent flight direction. There simply was not enough time to react to a clearance given at such an inopportune moment. The controller should have waited until after the intersection to give the clearance that was given.
My ipad had also went into sleep mode function and it took a few extra seconds to get into my Jeppesen charts and verify the crossing restrictions; I wish that function could be disabled on the ipad when in flight.
An aircraft climbing on the DEN EXTAN 4; was issued a clearance to FL230 just prior to the 10;000 feet of the KIDNG intersection constraint. This caused an overshoot when the FMS dropped the constraint after the altitude change.