Small aircraft on IFR flight plan has altitude deviation and manifold pressure gauge failure.

Attributes
ACN	287322
Time
Date	199411
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : n90 airport : teb
State Reference	NY
Altitude	msl bound lower : 5700 msl bound upper : 6600
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other ground : parked
Route In Use	enroute airway : n90
Flight Plan	IFR
Person 1
Affiliation	Other
Function	instruction : instructor
Qualification	pilot : cfi pilot : instrument pilot : commercial
Experience	flight time last 90 days : 120 flight time total : 750 flight time type : 10
ASRS Report	287322
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : clearance other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Departed een IFR for teb. Icing occurred at 3 times during the flight, requiring either a climb or descent. The wind was strong with a SIGMET issued for moderate to severe turbulence and low level wind shear. The person I was flying with owned the aircraft we were in and is also instrument rated. He was PIC of the whole flight. At times we had altdevs of 600- 300 ft. Partly due to the PIC's plting technique but mostly due to the conditions. Several times controllers asked us about our altitude or just gave us an altimeter setting. Just over the hudson river, or thereabouts, the manifold pressure gauge failed. This had no bearing on the outcome of the flight. Descending to teb we broke out at 3100 ft MSL and were hit with severe turbulence which made control very difficult. Several times we went through the approach but were in VFR condition at the time. We landed at teb without incident. The pilot was shaken up and I didn't look forward to returning unless conditions improved. A mechanic at FBO looked at the aircraft to make a diagnosis and fix the manifold pressure gauge.

Original NASA ASRS Text

Title: SMA ON IFR FLT PLAN HAS ALTDEV AND MANIFOLD PRESSURE GAUGE FAILURE.

Narrative: DEPARTED EEN IFR FOR TEB. ICING OCCURRED AT 3 TIMES DURING THE FLT, REQUIRING EITHER A CLB OR DSCNT. THE WIND WAS STRONG WITH A SIGMET ISSUED FOR MODERATE TO SEVERE TURB AND LOW LEVEL WIND SHEAR. THE PERSON I WAS FLYING WITH OWNED THE ACFT WE WERE IN AND IS ALSO INST RATED. HE WAS PIC OF THE WHOLE FLT. AT TIMES WE HAD ALTDEVS OF 600- 300 FT. PARTLY DUE TO THE PIC'S PLTING TECHNIQUE BUT MOSTLY DUE TO THE CONDITIONS. SEVERAL TIMES CTLRS ASKED US ABOUT OUR ALT OR JUST GAVE US AN ALTIMETER SETTING. JUST OVER THE HUDSON RIVER, OR THEREABOUTS, THE MANIFOLD PRESSURE GAUGE FAILED. THIS HAD NO BEARING ON THE OUTCOME OF THE FLT. DSNDING TO TEB WE BROKE OUT AT 3100 FT MSL AND WERE HIT WITH SEVERE TURB WHICH MADE CTL VERY DIFFICULT. SEVERAL TIMES WE WENT THROUGH THE APCH BUT WERE IN VFR CONDITION AT THE TIME. WE LANDED AT TEB WITHOUT INCIDENT. THE PLT WAS SHAKEN UP AND I DIDN'T LOOK FORWARD TO RETURNING UNLESS CONDITIONS IMPROVED. A MECH AT FBO LOOKED AT THE ACFT TO MAKE A DIAGNOSIS AND FIX THE MANIFOLD PRESSURE GAUGE.

Data retrieved from NASA's ASRS site as of July 2007 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.