Av Informasjonskomitéen
Det skjedde nylig en fatal ulykke med en Zenair CH601 XL i Nederland, og der har flytypen umiddelbart blitt satt på bakken for videre undersøkelser. De første resultatene viste at det hadde skjedd noe med vingene oppe i luften, og at det skjedde et strukturelt sammenbrudd. Fabrikken antar at dette skyldtes flutter på rorene, og foreskriver at kablene til alle rorene skal sjekkes for korrekt innstramming. Dersom disse er for løse vil flutter (voldsom og hurtig vibrasjon) kunne oppstå, med det resultat at roret kan løsne på et øyeblikk, og en kan dermed miste styringen. Dersom vingens innfestning bryter sammen blir ting langt verre, og kun en innmontert redningsskjerm kan redde liv og helse.
Den Nederlandske havarikommisjonen har gått et skritt lenger og satt alle CH 610 XL på bakken inntil man har blitt enige om hva som skal gjøres med flyet. De referer også til at det har skjedd 7 andre lignende tilfeller i verden uten at årsaken har kommet klart fram. Last ned den Nederlandske AD (Airworthiness Directive) her.
De som eier en slik XL maskin skal derfor av sikkerhetsmessige årsaker la flyet stå på bakken i påvente av den videre prosessen. Dere andre som har UL utgaven kan trøste dere med at vingekonstruksjonen er helt annerledes, og at en ikke har observert slike problemer på den den typen.
Den Nederlandske Havarikommisjonen sier dette:
Find attached an Emergency Airworthiness Directive which the Civil Aviation Authority of the Netherlands (CAA-NL) issued last week applicable to Zenair Zodiac CH 601 XL aircraft.
Background:
In September a fatal accident occurred with a Zodiac CH 601 XL micro
light. The preliminary investigation done by the Dutch Safety Board,
led to the conclusion that the wing fold up during flight (without
particular reason). According the report at least 7 similar
occurrences happened the past 2 years over the world with the Zodiac
CH601, but without a definite cause of the failure. Since the
investigation is still going on and the final report has not been
published yet, the Safety Board issued a warning to the aviation
community about possible risks imposed in operating the CH 601 XL.
CAA-NL then decided to issue emergency AD NL-2008-003 for grounding
the aircraft.
Kind regards,
Dirk-Jan de Lange
Transport and Water Management Inspectorate
Civil Aviation Authority Netherlands
Supervision Services / Unit Object Permits
P.O. Box 575
2130 AN Hoofddorp
The Netherlands
Telephone: +31. (70) 456 31 17
Telefax: +31. (70) 456 30 06
E-mail:
Mailto:info.register@ivw.nl
Zenair fabrikken:
Sjekk ut fabrikkens AD (Airworthiness Directive) som sier hvordan sjekken skal utføres. Brevet som de har sendt til alle sine forhandlere er gjengitt nedenfor.
To: All Zenair Dealers, Representatives and Promoters
From: Zenair Sarl/Zenair Ltd
Date: October 28, 2008
Subject: Mandatory Airworthiness Directive for the Zodiac XL:
#ZE-2008-01
In response to the preliminary findings of an investigation into the fatal accident of a Zenair CH 601XL in the Netherlands, Zenair is issuing the following mandatory airworthiness directive (AD) immediately applicable to all Zenair CH 601 XL aircraft.
Please note the mandatory nature of these instructions, and that they apply to all Zodiac XL models, whether registered as ultralights or as amateur-built. We request your assistance in making sure all owners and operators of this aircraft type are notified; all relevant customers should be informed about the actions called-for in A.D. No. ZE-2008-01.
Note that the directive does not provide new information regarding the aircraft; it requests verification of what should already be in place, namely, proper tension of the control cables. As indicated in a letter from Chris Heintz published this summer in the Zenair Newsletter, even a strong design like the CH 601 XL can be severely damaged by the onset of flutter.
The Zodiac XL continues to be a very sturdy and controllable light aircraft if flown within its design parameters. This intention of this AD is to confirm that a specific element of the control system of every Zodiac XL is properly installed and/or maintained.
Please explain the importance of this AD to your XL customers and
provide them with a translation if necessary. An important taskf or us
all at this time is to reassure the Zodiac XL community that the design
is as solid as ever. By double-checking that all control cables are
tight as required, the Zodiac design should continue to enjoy its
reputation as a sturdy and fun aircraft, with great control, amazing
visibility and great all-around capabilities.
Do not hesitate to call if you have additional questions.
Sincerely,
Michael Heintz
Zenair in Europe
Tel: 33-(0)3-59-38-96-19
Cell: 33-(0)6-46-30-43-30