A CE560 first officer reported the aircraft did not capture 2;400 feet on approach and while he was ...

Attributes
ACN	1199913
Time
Date	201408
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ
State Reference	US
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Make Model Name	Citation V/Ultra/Encore (C560)
Operating Under FAR Part	Part 135
Flight Phase	Initial Approach
Flight Plan	IFR
Component
Aircraft Component	Altitude Hold/Capture
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Flight Engineer Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 90 Flight Crew Total 28700 Flight Crew Type 505
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Altitude Overshoot Deviation - Altitude Crossing Restriction Not Met Deviation - Procedural Published Material / Policy Inflight Event / Encounter CFTT / CFIT

Narrative:

Captain was on an intercept heading to join the ILS xxr. We were assigned 2;400 feet to join the ILS xxr. I was making a first officer instrument sub panel change and was head down and noticed the jet at 1;750 feet when it should have been 2;400. At the same approach noticed it and repeated the assigned altitude. That was my first time in the right seat on the citation V. Previous limited in training with the company was left seat only. It was also my first revenue flight with the company. I did fly both seats in the CE500 in the early 1980's. We landed without further incident but we did not have the terrain separation desired while at that altitude. There was no other traffic that time of night fortunately. Later that night when I flew 2 legs I did notice that that the autopilot would not always capture altitudes while descending with altitude select annunciated. Possible contributing factor was the short notice flight assignment on a late night mission.

Original NASA ASRS Text

Title: A CE560 First Officer reported the aircraft did not capture 2;400 feet on approach and while he was heads down the Captain allowed a descent to 1;750 feet before both he and ATC alerted about the deviation.

Narrative: Captain was on an intercept heading to join the ILS XXR. We were assigned 2;400 feet to join the ILS XXR. I was making a First Officer instrument sub panel change and was head down and noticed the jet at 1;750 feet when it should have been 2;400. At the same Approach noticed it and repeated the assigned altitude. That was my first time in the right seat on the Citation V. Previous limited in training with the company was left seat only. It was also my first revenue flight with the company. I did fly both seats in the CE500 in the early 1980's. We landed without further incident but we did not have the terrain separation desired while at that altitude. There was no other traffic that time of night fortunately. Later that night when I flew 2 legs I did notice that that the autopilot would not always capture altitudes while descending with altitude select annunciated. Possible contributing factor was the short notice flight assignment on a late night mission.

Data retrieved from NASA's ASRS site 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 CE560 first officer reported the aircraft did not capture 2;400 feet on approach and while he was heads down the captain allowed a descent to 1;750 feet before both he and ATC alerted about the deviation.