A B737-800 captain reported that the number 2 navigation radio head failed precluding an ILS and sub...

Narrative:

Enroute to bos; #2 navigation radio head failed [to] tune. The new frequency on the right side would change but would not switch to the active side. Since the left ILS frequency could not be set; the RNAV (GPS) 22L was selected; briefed; requested and flown. When we were cleared for the approach; the approach mode would not select. Despite numerous attempts to select approach; no guidance was achieved. Fortunately; we were in VFR conditions and an uneventful visual approach to touchdown was flown. The fom briefing flow charts and briefing cards were utilized during the brief. Neither the first officer nor I could figure out why the approach mode would not engage. A maintenance entry was made but the autopilot systems checked normally. I still have no idea why the approach was not successful. Systems training on the 737 is poor to nonexistent. I feel ill equipped to understand or predict what the aircraft will do in any degraded system mode. A modern multimedia systems training course should be designed and implemented to increase pilot systems knowledge of the aircraft.

Original NASA ASRS Text

Title: A B737-800 Captain reported that the number 2 NAV radio head failed precluding an ILS and subsequently the APP mode would not arm for the RNAV (GPS) approach so a visual approach was completed.

Narrative: Enroute to BOS; #2 Navigation radio head failed [to] tune. The new frequency on the right side would change but would not switch to the active side. Since the left ILS frequency could not be set; the RNAV (GPS) 22L was selected; briefed; requested and flown. When we were cleared for the approach; the approach mode would not select. Despite numerous attempts to select approach; no guidance was achieved. Fortunately; we were in VFR conditions and an uneventful visual approach to touchdown was flown. The FOM briefing flow charts and briefing cards were utilized during the brief. Neither the First Officer nor I could figure out why the approach mode would not engage. A maintenance entry was made but the autopilot systems checked normally. I still have no idea why the approach was not successful. Systems training on the 737 is poor to nonexistent. I feel ill equipped to understand or predict what the aircraft will do in any degraded system mode. A modern multimedia systems training course should be designed and implemented to increase pilot systems knowledge of the aircraft.

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	987840
Time
Date	201201
Local Time Of Day	1201-1800
Place
Locale Reference	BOS.Airport
State Reference	MA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	IFR
Component
Aircraft Component	VHF
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 200 Flight Crew Total 11000 Flight Crew Type 1317
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Other / Unknown

A B737-800 captain reported that the number 2 navigation radio head failed precluding an ILS and subsequently the app mode would not arm for the RNAV (GPS) approach so a visual approach was completed.