Silva SEAWIND 3000 N465W

Summary

On 3 April 1993 at about 14:55 local time, a Silva SEAWIND 3000 registered N465W was involved in an accident near Coatesville, Pennsylvania, United States. 2 people were on board and one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

3 April 1993 at 14:55

Classification

Accident

Location

Coatesville, Pennsylvania, United States

Nearest airport

Chester County (40N)

Coordinates

39.9808, -75.8105

Aircraft

Silva SEAWIND 3000

Registration

N465W

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Unknown

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

NYC93LA067

1 person had minor injuries.

IMPROPER ADJUSTMENT SETTING OF THE PROPELLER PITCH CHANGE MECHANISM AND/OR PROPELLER GOVERNOR OUTPUT PRESSURE, WHICH RESULTED IN A LOSS OF POSITIVE THRUST AND A FORCED LANDING.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

THE KIT PLANE WAS ON A TEST FLIGHT WITH A HARTZELL LIMITED PRODUCTION/CONSTANT SPEED/NON-FEATHERING/FULL REVERSING PROP. THE PILOT STATED THAT IN THE 1ST POWER-OFF GLIDE, HE SET THE THROTTLE TO IDLE & THE PROP TO LOW PITCH; ABOUT 10 TO 15 SEC LATER, THE ENGINE RACED & THE PROP APPEARED TO GO TO ZERO PITCH. HE SAID MOVEMENT OF THE PROP CONTROL & THROTTLE HAD NO EFFECT; THE PASSENGER SAID THE THROTTLE WAS ADVANCED & RPM OVERSPED EVEN MORE. ALTITUDE COULD NOT BE MAINTAINED & A FORCED LANDING WAS MADE ON ROUGH TERRAIN. AN INVESTIGATION REVEALED THE PROP BLADE ANGLE LIMITS WERE WITHIN THE PRESCRIBED -15 TO +26.2 DEG LIMITS. THE LOW PITCH BLADE ANGLE WAS SET FOR 3.7 DEG, BUT SPECIFICATIONS FOR TYPICAL HARTZELL & LYCOMING ENGINE COMBINATIONS HAD LOW PITCH BLADE ANGLES RANGING FROM 12 TO 13.5 DEG. TESTING OF THE PROPELLER DISCLOSED THAT THE CENTRIFUGAL LOW PITCH START LOCKS WOULD NOT ENGAGE, IF THE GOVERNOR OIL PRESSURE REMAINED AT OR ABOVE 120 PSI AFTER START LOCK DISENGAGEMENT.

Quoted verbatim from the NTSB record.