Coniston Water per hour () in "Blue Bird K4". Between 1956 and 1959 Sir Malcolm's son Donald Campbell set four successive records on the lake in "Bluebird K7", a hydroplane. In 1966 Donald Campbell decided that he needed to exceed 300 miles per hour (483 km/h) in order to retain the record. On 4 January 1967, he achieved a top speed of over 320 miles per hour () in "Bluebird K7" on the return leg of a record-breaking attempt. He then lost control of "Bluebird", which somersaulted and crashed, sinking rapidly. Campbell was killed instantly on impact when decapitated by the K7's
Not-To-Exceed is designed to focus on compliance in the real world, and relies on emissions testing, utilizing Portable Emissions Measurement Systems (PEMS) with NOx, HC, CO and PM being the pollutants to be measured. Measurement Accuracy Margins are being established to account for the emissions measurement variability associated with the PEMS in-use. Not-To-Exceed The Not-To-Exceed (NTE) standard promulgated by the United States Environmental Protection Agency (EPA) ensures that heavy-duty truck engine emissions are controlled over the full range of speed and load combinations commonly experienced in use. NTE establishes an area (the "NTE zone") under the torque curve of an engine