* Aker BP may have impairments in Q2 - CEO
* Maintenance to cut output by 30,000 boepd in Q2
* CEO dampens expectations of early Johan Sverdrup startup(Adds CEO quotes, details)
OSLO, April 26 (Reuters) - Norway's Aker BP, anoil firm partly owned by BP, posted on Friday a biggerthan expected fall in operating earnings in first quarter, afterimpairments in the Ula area of the North Sea and higherexploration costs.
Chief Executive Karl Johnny Hersvik also told Reuters therecould be more impairments related to "technical goodwill" at theUla area in the second quarter.
Earnings before interest and taxes (EBIT) for the firstthree months fell to $286.5 million from $505 million in thesame quarter a year ago, compared to $303 million expected byanalysts in a Reuters poll.
The company said it booked an impairment of $68.9 million inthe first quarter due to a change in expected costs andproduction profiles for future development in the Ula area. Ithad no impairments in the same quarter a year ago.
Hersvik also said the company was considering adding a newplatform at the field in mid-2020s with the concept selectionlikely to be made by the end of this year.
The drilling of two dry wells out of three led the companyto expense $90.4 million in exploration costs in the quarter, upfrom $54.7 million a year ago, it said.
It plans to drill a total of 15 exploration wells, includingpartner-operated wells, in 2019.
Aker BP's revenues were also affected by realised oil andgas prices falling 6 percent from a year ago, while productionwas almost unchanged at 158,700 barrels of oil equivalents perday (boepd).
Aker BP repeated its full-year production guidance at155,000 to 160,000 boepd.
Chief Financial Officer David Torvik Toenne said output inthe second quarter could fall by about 30,000 boepd due toturnarounds at Valhall and Ula.
Production should rise by a similar volume in the lastquarter once Norway's giant Johan Sverdrup oilfield starts up,he said.
Aker BP has an 11.6 percent stake in the Equinor-operatedJohan Sverdrup field, which is expected to start inNovember. The field's reserves are estimated at 2.2 billion to3.2 billion barrels.
"There are no reasons to predict earlier startup. There isstill a lot of work to be done in terms of testing andcommissioning," Hersvik told a news conference, seeking todampen some analysts' expectations for an earlier startup.(Reporting by Nerijus Adomaitis, editing by Terje Solsvik andDarren Schuettler)
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