58-17-04: Water Rudder Modification

FAA order 58-17-04 is an airworthiness directive. The FAA's subject line: Water Rudder Modification. It names Piaggio P.136-L1: about 6 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: flight controls.

What it applies to as the FAA lists it

Kind of product: Aircraft
Makes: Piaggio & C.
Models: P.136-L1, P.136-L2
On this site: Piaggio P.136-L1 6 registered

Dates and paperwork

Docket: Unknown
Status: Current
The FAA's document: Read the order on the FAA's site

The order itself the regulatory text, as published

Show the full text (833 characters)

58-17-04	PIAGGIO:  Applies to All Models P.136-L1 and P.136-L2 Aircraft. 
	Compliance required by December 1, 1958. 
	Several cases have occurred where the water rudder inadvertently dropped into the extended position during water landings.  In order to avoid future occurrences, Piaggio & Co. recommends that a hook be incorporated at the water rudder retraction cylinder, which is controllable by the pilot. 
	In addition, the forward section of the water rudder should be cut off, in order to prevent any interference with the retraction of the water rudder because of the accumulation of debris. 
	This modification is considered mandatory by the Registro Aeronautico Italiano.  The FAA concurs and considers compliance therewith mandatory. 
	(Piaggio & Co. Change Order No. 36 L-42, dated May 29, 1958, covers the same subject.)

Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 5, 2026. Connections as data: /graph/directive/58-17-04.json · aircraft systems.