The phrase "a fifth engine for" is correct and usable in written English.
It can be used when referring to an additional engine in a series or a specific context, such as in technology, transportation, or manufacturing.
Example: "The company announced plans to develop a fifth engine for their new line of aircraft, promising improved fuel efficiency."
Alternatives: "an additional engine for" or "a new engine for".
The 2010 military bill, for example, contained expenditures that the Pentagon did not want: $2.5 billion for C-17 transport planes; $825 million for all-terrain vehicles; $732 million for other planes, and $500 million for a second engine for the F-35 jet.
The party's fiscal hawks teamed up with Democrats, for example, to approve an amendment that would scrap a programme to develop a second engine for a military jet.Tim Geithner, the secretary of the treasury, said the cuts would "damage our capacity to create jobs and expand the economy".
By September another cable was reporting that the Dutch defence minister was concerned over the omission from the 2010 US defence budget of a second engine for the JSF (F-136), in which it said Dutch industry had "high value" contracts.
Although the Sustainable Defense Taskforce that he chaired back in 2011 recommended more than $1 trillion in cuts over 10 years, Frank himself voted for Congress to contract with General Electric and Rolls Royce for a second engine for the already over-priced F-35.
Toro Rosso's Daniil Kvyat has a 10-place penalty for taking a seventh engine of the season.
Her propensity for error is a second engine of sympathy.
Background: 2. (U) The concept of having two competing engines for the JSF dates back to the "Great Engine War," when Congress funded the development of a second engine in 1979 for the Air Force's fighter aircraft.
Vettel, meanwhile, knows he will face a difficult race as a result of Red Bull needing to fit a sixth engine to his car for the remainder of the season, which means a pit-lane start as a penalty.
The top three criteria were response time (the time before the company's first engine arrives at a fire); the time that it takes for a second engine to arrive; and the number of fires in occupied buildings to which the company responded.
Red Bull's Ricciardo was sixth, and his team-mate Sebastian Vettel 18th and last as the world champion just prepared for the race - a penalty for taking a sixth engine this season means he has to start from the pit lane.
