Net catastrophe losses dropped to $22.1 million compared to $58.7 million in last year's second quarter.

For the first half of the year, Aspen reports net income after tax of $251.2 million, up from $131.9 million in the first half of 2013.

Chris O'Kane, CEO, says in a statement, “Aspen's strong, high-quality results fort he second quarter and first half of 2014 demonstrate the benefits of the investments we have made in our business, our operating focus and our successful strategy to manage a dynamic market.”

He credits the results to “top-line growth, sound underwriting, impressive performance in our reinsurance business and increasing scale” in the company's U.S. insurance platform.

Stern Agee analysts Dan Farrell and Nitin Chhabra say Aspen's underwriting results are in line with guidance, and that Aspen's reported operating earnings per share of $1.40 is slightly above recent guidance range.

Gross written premiums were within the company's guidance, Stern Agee adds, but net written premium was lower.

Aviation war-risk rates should rise

In a conference call, O'Kane noted headwinds in the market, namely continued low investment returns and rate pressure in some insurance and reinsurance lines. He said, “Within insurance, aviation and energy property are the most profoundly affected.” But he noted the recent Malaysia Airlines losses should put “meaningful upwards pressrue on the aviation war accounts.” He says Aspen will push for increases of 100% for primary aviation war risks. For reinsurance, aviation war risk rate increases could be in the 200%-300% range.

But O'Kane said he doesn't expect the rate increases for war risks to spread to primary avation hull risks.