Thomas E. Stiehle
Executive Vice President and Chief Financial Officer at Huntington Ingalls Industries
Thanks Chris and good morning. Today I'll briefly review our second quarter results. For more detail on the segment results please refer to the earnings release issued this morning and posted to our website. Beginning with our consolidated results on slide six of the presentation our second quarter revenues of approximately $3 billion increased 6. 8% Compared to the same period last year and represent a record second quarter result for HII. This increased revenue was attributable to very strong year-over-year revenue growth of nearly 19% at Mission Technologies as well as growth at Ingalls and Newport News shipbuilding.
Operating income for the quarter of $189 million increased by $33 million or 21.2% from the second quarter of 2023. And operating margin of 6.3% compares to operating margin of 5.6% in the same period last year. Net earnings in the quarter were $173 million compared to $130 million in the second quarter of 2023. Diluted earnings per share in the quarter were $4.38 compared to $3.27 in the second quarter of the prior year representing a year-over-year growth of approximately 34%. Backlog increased slightly to end the quarter at $48.5 billion up approximately $100 million from Q1's close.
Moving to slide seven. Ingall's revenues of $712 million in the quarter increased $48 million or 7.2% from the same period last year driven primarily by higher volumes in amphibious assault ships and surface combatants partially offset by lower volumes in the National Security Cutter program. Ingalls operating income for the quarter was $56 million and operating margin of 7.9% compared to $65 million and 9.8% respectively from the same period last year. The decreases were primarily due to lower risk retirement on surface combatants partially offset by a delivery contract incentive on LP 29 Richard M. McCool Jr.
At Newport News revenues of $1.5 billion were up $26 million or 1.7% from the same period last year. Newport News operating income for the quarter was $111 million and operating margin was 7.2% compared to $95 million and 6.3% respectively in the prior year period. The increases were primarily driven by favorable contract adjustments incentives and volume on the RCOH program partially offset by lower performance on aircraft carrier construction and the VCS program. Shipbuilding operating margin in the second quarter was 7.4% up from 6.8% in Q1 of this year. We are pleased to exceed the shipbuilding margin guidance we previously provided for the quarter and we continue to see significant opportunity in the second half of the year for margin enhancement.
At Mission Technologies revenues of $765 million increased $120 million or 18.6% compared to the second quarter of 2023 primarily due to higher volumes in C5ISR and cyber electronic warfare and space. A portion of Mission Technologies overperformance in the quarter was driven by material and work that may not reoccur on a consistent basis and we have factored that into our guide going forward. We are obviously very pleased with the growth in the quarter and we are raising the Mission Technologies revenue guidance range for the year by $50 million.
Mission Technologies operating income for the quarter was $36 million and operating margin was 4.7% compared to $9 million and 1.4% respectively in the second quarter of last year. The increases were driven primarily by higher volumes I just mentioned as well as stronger performance in fleet sustainment. In addition in the second quarter of 2023 we recorded a $6 million loss related to the sale of a joint venture interest which also helps the year-over-year comparison. Second quarter results for Mission Technologies included approximately $25 million of amortization of purchased intangible assets. Mission Technologies EBITDA margin in the second quarter was 8.5% compared to 6.7% in the second quarter of 2023 and 7.7% last quarter.
Turning to slide eight. Cash used in operations was $9 million in the quarter. Net capital expenditures were $90 million or 3% of revenues. Free cash flow in the quarter was negative $99 million consistent with the guidance we provided on the first quarter call. Cash contributions to our pension and other postretirement benefit plans were $14 million in the quarter. Also during the quarter we paid dividends of $1.30 per share or $51 million in aggregate. We also repurchased approximately 250000 shares during the quarter at a cost of approximately $65 million.
Moving to slide nine. We have summarized our expectations for the third quarter and the year. For the third quarter we expect shipbuilding revenue of approximately $2.2 billion and shipbuilding margin of approximately 7.8% with margin continuing to ramp in the fourth quarter. For Mission Technologies we expect revenues of approximately $650 million and operating margin of approximately 2.5%. For the year we are reaffirming our share building revenue and margin expectations and as I previously noted we are raising Mission Technologies revenue guidance range.
We are also updating our interest expense expectation to $95 million based on the phasing of our latest cash flow forecast. We are reiterating our free cash flow outlook for 2024 of $600 million to $700 million as well as our five-year free cash flow outlook of $3.6 billion. As we have noted we expect free cash flow to be weighted towards the latter part of the year which is not unusual. We currently expect third quarter free cash flow to be near zero preceding expected strong cash collections in the fourth quarter.
To summarize we delivered another quarter of strong year-over-year revenue growth and met our shipbuilding expectations while Mission Technologies portfolio continues to perform very well. Additionally we are pleased to raise our Mission Technologies revenue guidance and reaffirm our shipbuilding financial outlook for the year.
With that I'll turn the call back over to Christie to manage Q&A.