After an abortive evaluation two years ago of an in-house design and one developed by Winglet Technology of the USA, Airbus revealed in May that it intended to re-examine the concept in conjunction with Boeing's long-established supplier API. These tests were originally due to start in July, but will now get under way imminently, says the airframer.
Agreement was reached with API "in the last few days" to perform the flight tests, says Airbus. "The aircraft will be prepared in the coming days and the reference flights without winglets will follow," it adds. "The winglets will then be installed and the flight tests with winglets performed."
Airbus says that the detailed schedule is still being finalised, and adds: "The fact that we are performing the tests does not indicate that we intend to offer API winglets."
The airframer's evaluation in 2006 - which included back-to-back tests of the winglet-equipped Airbus development A320 and a modified production aircraft belonging to JetBlue - had the target of finding "a couple of percent" performance gain.
However at the time Airbus could not find sufficient improvement to offset the weight increase caused by the strengthening required.
For the tests of the API blended winglets the airframer will strengthen the A320's wingtips for the test with doublers but hopes that the programme's ongoing weight-reduction effort will help counter the strengthening. A decision whether to launch the upgrade programme is expected before the end of the year.