The burden would fall mostly on high frequency traders while having minimal impact on long-term investors such as pension funds.

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Ranger IV was also equipped with a seismometer and radio transmitter, designed to be released in a small capsule from the rocket before impact and land on the Moon in sufficiently good condition to measure the frequency of natural earthquakes in the body of the Moon.

BBC: 1962: First US rocket lands on Moon

So the operational impact of any engine-related grounding is decreased by having competing engines, but the frequency of engine-related groundings is probably increased.

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Delta is also cutting its weekly frequency between Atlanta and Detroit to Mexico City due to the flu's impact on consumers' travel plans.

CNN: Delta cutting capacity, blames rising fuel prices, H1N1 virus