(Reuters) - Senior Plc (>> Senior plc), a maker of parts for aircraft and automobiles, said its group chief executive, Mark Rollins, would retire in the first half of 2015.

The FTSE-250 <.FTMC> company's shares fell as much 2.8 percent on the London Stock Exchange on Monday.

Rollins, 65, has spent 17 years at Senior, including seven as chief executive. He said the recruitment process for a successor was already underway.

In a note to research analysts, Rollins said he was a strong believer in fresh blood at the top.

Jefferies analyst Andrew Douglas told Reuters that Rollins' exit had created uncertainty in the minds of investors.

"We are disappointed that... Rollins is due toretire in 1H15 and expect the uncertainty to impact the shares in the short-term until a successor is found," Investec analyst Thomas Rands wrote in a note.

Senior also reported first-half earnings on Monday.

The maker of hydraulic parts, seal assemblies and aircraft wall panels said its pretax profit rose to 45.1 million pounds for the six months ended June 30, from 37.1 million pounds last year.

Revenue was nearly flat at 400.4 million pounds, hurt by a stronger pound. The company generated more than half its revenue from North America in the first six months of the year.

A strengthening sterling has dented first-half earnings at a number of British industrials.

The pound has risen 3.3 percent against the dollar in the first-half of the year to June 30.

Rollins told Reuters that he expected Senior's full-year profit to fall by about 7 percent due to the rising pound.

The company's aerospace division, which accounts for two-thirds of its total revenue, has been benefitting from higher demand from the commercial aviation sector.

The commercial aviation business grew to about 39 percent of group sales in the first half, from 34 percent a year earlier, driven primarily by a 7 percent rise in aircraft deliveries by Boeing (>> The Boeing Company) and Airbus (>> AIRBUS GROUP), Senior said.

Net orders from the aviation giants increased 22 percent, with their combined order book rising to 10,783 aircraft.

Senior shares were down 2.3 percent at 256.4 pence at 12:40 BST.

(Reporting by Aashika Jain in Bangalore; Editing by Gopakumar Warrier and Simon Jennings)

By Aashika Jain

Stocks treated in this article : AIRBUS GROUP, The Boeing Company, Senior plc