B737-800 first officer; late to recognize slow autothrottle response after raising the pitch attitud...

Narrative:

Prior to top of descent; I briefed that I would fly the visual approach to runway xx backed up by the localizer DME approach. Landing configuration would be flaps 30 and brake setting #3. We were cleared the visual to runway xx by approach at 3;000 feet MSL. I decided to start slowing and configuring early and the aircraft was properly configured and on reference speed of 148 KTS plus 5 KTS; approaching the FAF. The aircraft position was slightly high on visual glide path; so I disengaged the autopilot; left autothrottles engaged; and started a descent to capture normal glide path. The throttles reduced and the nose was lowered. When I raised the pitch attitude once the normal visual glide path was attained; I did not notice the autothrottles did not advance. With the raising of the pitch attitude; the airspeed decreased 15-20 knots below reference speed. The captain announced; 'airspeed' and I immediately overrode the autothrottles and increased power. The flight path continued on a slight descent when power was increased. As the airspeed increased; I raised the pitch attitude to level flight and we regained proper pitch; power; airspeed and glide path at approximately 800 feet to 1;000 feet AGL. All stabilized approach criteria were met before the 500 feet [required] for VMC approaches. Landing and taxi in were completely uneventful. Automation is a great tool and works as expected 95% of the time. I would say that pilots can be 'lulled' into a sense of security when using it. All the automation in the world does not relieve us of the charge to fly the airplane at all times. Closer monitoring of approach speed and faster realization of the 'lag' of the autothrottles would have prevented the decrease in airspeed. Had the situation progressed further; a go-around was; without a doubt; the proper action. Needless to say; one must remain vigilant in monitoring and assessing all flight parameters at all times. It's the times when you think you have things 'wired' that you need to maintain total awareness.

Original NASA ASRS Text

Title: B737-800 First Officer; late to recognize slow autothrottle response after raising the pitch attitude on approach; responded to the Captain's 'airspeed' callout and overrode the autothrottles to increase power. Approach was stabilized and preceded uneventfully.

Narrative: Prior to top of descent; I briefed that I would fly the visual approach to RWY XX backed up by the Localizer DME approach. Landing configuration would be Flaps 30 and Brake Setting #3. We were cleared the visual to RWY XX by Approach at 3;000 feet MSL. I decided to start slowing and configuring early and the aircraft was properly configured and on reference speed of 148 KTS plus 5 KTS; approaching the FAF. The aircraft position was slightly high on visual glide path; so I disengaged the autopilot; left autothrottles engaged; and started a descent to capture normal glide path. The throttles reduced and the nose was lowered. When I raised the pitch attitude once the normal visual glide path was attained; I did not notice the autothrottles did not advance. With the raising of the pitch attitude; the airspeed decreased 15-20 knots below reference speed. The Captain announced; 'Airspeed' and I immediately overrode the autothrottles and increased power. The flight path continued on a slight descent when power was increased. As the airspeed increased; I raised the pitch attitude to level flight and we regained proper pitch; power; airspeed and glide path at approximately 800 feet to 1;000 feet AGL. All stabilized approach criteria were met before the 500 feet [required] for VMC approaches. Landing and taxi in were completely uneventful. Automation is a great tool and works as expected 95% of the time. I would say that pilots can be 'lulled' into a sense of security when using it. All the automation in the world does not relieve us of the charge to fly the airplane at all times. Closer monitoring of approach speed and faster realization of the 'lag' of the autothrottles would have prevented the decrease in airspeed. Had the situation progressed further; a go-around was; without a doubt; the proper action. Needless to say; one must remain vigilant in monitoring and assessing all flight parameters at all times. It's the times when you think you have things 'wired' that you need to maintain total awareness.

Data retrieved from NASA's ASRS site as of July 2013 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.

Attributes
ACN	1104998
Time
Date	201307
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Tower
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Component
Aircraft Component	Autothrottle/Speed Control
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Total 5
Events
Anomaly	Deviation - Procedural Published Material / Policy Deviation - Speed All Types

B737-800 first officer; late to recognize slow autothrottle response after raising the pitch attitude on approach; responded to the captain's 'airspeed' callout and overrode the autothrottles to increase power. Approach was stabilized and preceded uneventfully.