Whereas high speeds generally cannot be achieved by ramjets without their initially being assisted by a rocket, a scramjet, or supersonic combustion ramjet, can attain high speeds by reducing airflow compression at the entrance of the engine and letting air pass through at supersonic speeds.
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AWhereas high speeds generally cannot be achieved by ramjets without their initially being assisted by
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BWhereas a ramjet generally cannot achieve high speeds without the initial assistance of
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CWith ramjets, high speeds generally are not able to be achieved without initially being assisted by
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DUnlike with ramjets, generally unable to achieve high speeds without the initial assistance of
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EAlthough a ramjet generally does not have the capability of achieving high speeds without the initial assistance from
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