Japan has invested a huge sum on building up a simulated altitude test facility.

日本斥巨资建立发动机模拟高空试验台。

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Following hundreds hours of altitude test of a turbofan engine at different conditions, it has proved that the reconstruct ion is effective.

某涡扇发动机数百小时的各飞行状态高空模拟试验证实，改造成功有效。

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So far, apart from some low-altitude test flights, the only stratospheric tests have involved a scaled-down version tethered to a weather balloon.

目前对飞船只进行了一些低海拔的飞行测试，平流层的测试则仅仅是由气象探测气球负载着规模缩小的模型原型机来进行的。

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If a wine can pass the altitude taste test and make it on board, the producing vineyard has a great opportunity to broaden its market.

CNN: Grape expectations: Making wine taste good at 35,000 feet

However, Ponting questioned the validity of a seven-match series with every other major Test-playing nation in South Africa preparing at altitude for the two-week tournament.

BBC: Ashes loss still hurts - Ponting

It will take about three months for Nasa engineers to test the platform and get it ready for use at its operational altitude of 705km.

BBC: Lift-off for latest Landsat mission