Revenue was $1.2 billion and in line with expectations, while EBITDA, EBITDA margin and earnings per share exceeded our expectations.
Adjusted EBITDA was $272 million, and adjusted EBITDA margin was on par with Q1 2021 and Q4 2020 at 22.8% despite the addition of costs to prepare for the second half ramp-up in commercial aerospace production.
Earnings per share, excluding special items, was $0.22 and ahead of our expectations.
The increased operating performance focus of Howmet has led to improved margins, enhanced working capital control and capital discipline, which generated $160 million of cash in the first half of the year.
Year-to-date, we have reduced debt by approximately $835 million by completing the early redemption of the 2021 notes in Q1 and the 2022 notes in Q2 with cash on hand.
These transactions reduced 2021 interest expense by approximately $28 million and approximately $47 million on an annual run rate basis.
In the second quarter, we continue to return money to shareholders with the completion of a $200 million share buyback program.
The weighted average acquisition price was $34.02 per share for approximately 5.9 million shares.
The second quarter end cash balance was $716 million.
Year-to-date, we have reduced our pension and OPEB liabilities by approximately $160 million.
Moreover, full year pension and OpEx expense is expected to improve approximately 50% compared to last year.
Q2 revenue was 5% less year-over-year and in line with our expectations.
On a year-over-year basis, commercial aerospace was 31% less, driven by lower aircraft builds, spares and the lingering effects of customer inventory corrections.
Commercial aerospace continues to represent approximately 40% of total revenue compared to pre-COVID levels of 60%.
The industrial gas turbine business continues to grow and was up 13% year-over-year, driven by new builds and spares.
The commercial transportation business was up 89% year-over-year as it rebounds from customer shutdowns in Q2 of 2020.
Structural cost reductions are also in line with expectations with a $37 million year-over-year benefit which reflects the decisive actions we started in the second quarter of 2020 at the onset of the pandemic and continued through last year.
Year-to-date structural cost reductions are $98 million, which have essentially achieved already our target of approximately $100 million.
The aerospace decremental operating margins continue to be very good at only 19%, while the Wheels segment had an incremental margin of 47%.
EBITDA margin expanded by 310 basis points year-on-year, driven by price, variable cost flexing and fixed cost reductions.
Capital expenditure was $36 million for the quarter and continues to be less than depreciation and amortization, resulting in a net source of cash.
Lastly, free cash flow was $164 million for the quarter, resulting in a record first half.
Adjusted EBITDA margin for the quarter was 22.8% and consistent with the last couple of quarters on approximately $43 million of less revenue.
Q2 revenue at $1.2 billion was in line with expectations.
You can see the benefit of our actions since the start of the pandemic in Q2 with a solid 310 basis points EBITDA margin expansion, while revenue was approximately $58 million less in the same period.
Second quarter revenue was 5% less, driven by commercial aerospace, which continues to represent approximately 40% of total revenue in the quarter.
Commercial aerospace was 31% less year-over-year, in line with our projections as expected inventory corrections continued.
Defense aerospace was essentially flat in the second quarter as we are on a diverse set of programs with the Joint Strike Fighter being approximately 40% of the total defense business.
Commercial transportation, which impacts both the Forged Wheels and the Fastening Systems segments, was up 89% year-over-year as second quarter of last year was significantly impacted by customer shutdowns.
Finally, the industrial and other markets, which is composed of IGT, oil and gas and general industrial, was up 13%.
IGT, which makes up approximately 45% of this market, continues to be strong and was up a healthy 13% year-over-year.
As expected, Engine Products year-over-year revenue was 7% less in the second quarter.
Commercial aerospace was 17% less, driven by customer inventory corrections and reduced demand for spares.
Commercial aerospace was partially offset by a year-over-year increase of 13% in IGT.
Decremental margins for engines were 12% for the quarter as we hired back approximately 300 workers to prepare for the anticipated growth in the second half of this year.
Also was expected, Fastening Systems year-over-year revenue was 20% less in the second quarter.
Commercial aerospace was 42% less.
The industrial and commercial transportation markets within the Fastening Systems segment were both up approximately 45% year-over-year.
Decremental margins for Fastening Systems were 31% for the second quarter, and segment operating profit margin was approximately 19%.
Engineered Structures year-over-year revenue was 30% less in the second quarter.
Commercial aerospace was 45% less, driven by customer inventory corrections and production declines for the Boeing 787.
Decremental margins for Engineered Structures were 12% for the quarter.
On a sequential basis, volumes were down approximately 7% due to customer supply chain issues.
Reported revenue was essentially flat sequentially, driven by a 20% increase in aluminum prices.
Segment operating profit margin was approximately 27%, and year-over-year incremental margin was 47%.
Gross debt stands at approximately $4.2 billion.
Finally, our $1 billion 5-year revolving credit facility remains undrawn.
Special items for the second quarter were a net charge of approximately $22 million, mainly driven by the costs associated with the early redemption of the 2022 bonds completed in early May.
For 2020, we had a 20% year-over-year improvement in rate to 0.71.
Additionally, 84% of our locations worldwide were without a lost workday incident.
Recently, we were recognized by the 50/50 Women on Boards organization for our commitment to board diversity.
For commercial aerospace, next-generation jet engine technology reduces fuel consumption by approximately 15%.
Moreover, Howmet's increased content on composite aircraft of 2 times contributes to lightweighting solutions and reduces fuel use as composite aircraft are approximately 20% more fuel efficient than comparable metallic aircraft.
For Forged Wheels, Howmet's aluminum wheels are 5 times stronger than steel while being 47% lighter.
Customers can realize up to 1,400 pounds of weight savings from retrofitting an 18-wheeler Class eight truck of steel to aluminum wheels.
For IGT, Howmet's products continue to enable higher operating temperatures in the turbine and also pressures, which increase the load efficiency toward approximately 64% and reduce nitrogen oxide emissions by approximately 40%.
Lastly, for renewables, Howmet's Fastening Systems used with solar panels improve strength and clamping by 5 times to 10 times and reduce installation time by up to 80%.
The expectation that Howmet will transition into revenue growth in the third quarter continues with growth of approximately 15% in commercial aerospace and total revenue growth of approximately 9%.
In terms of specific numbers, we expect the following: for the third quarter, revenue of $1.3 billion, plus or minus $20 million; EBITDA of $295 million, plus or minus $10 million; EBITDA margin of 22.7%, plus or minus 40 basis points; and earnings per share of $0.25, plus or minus $0.02.
And for the year, we expect revenue to be $5.1 billion, plus or minus $50 million; EBITDA baseline to increase to $1.17 billion, plus or minus -- plus $15 million, minus $25 million; EBITDA margin to increase to 22.9%, plus 10 basis points and minus 20 basis points; earnings per share increase to $0.99, plus or minus $0.03; cash flow baseline increase to $450 million, plus or minus $35 million.
Moving to the right-hand side of the slide, we expect the following: second half revenue to be up approximately 12% versus the first half, driven by commercial aerospace, defense and IGT; second half year-over-year incremental margins of over 50% compared to the prior year.
The cost reduction carryover of $100 million is already achieved with some potential modest upside.
Pension and OPEB contributions of approximately $120 million.
We are reducing cash pension contributions by approximately $40 million based upon the American Rescue Plan Act.
capex should be in the range of $200 million to $220 million compared to depreciation of approximately $270 million.
Adjusted free cash flow conversion continues to be in excess of net income at approximately 100%.
Lastly, as announced last month, we have reinstated the quarterly dividend of $0.02 per common stock, starting in the third quarter.
The net recruitment of production operators in the second quarter was approximately 300 people, principally in our Engine business.
In the second half, we plan to recruit another net 500 people.
The third quarter outlook is for revenue to be approximately $100 million higher than the second quarter with margins somewhere between 22.3% and 23.1%.
However, year-over-year incremental margins are expected to be over 50%.
Consolidated EBITDA margins for the second half are expected to be 22.6% to 23.2%, setting a platform for a healthy 2022 And overcoming the drag of the increased labor costs from the recruitment I talked about and the cost of net -- the net effect of the metal recoveries.

Summary:
Revenue was $1.2 billion and in line with expectations, while EBITDA, EBITDA margin and earnings per share exceeded our expectations.
Earnings per share, excluding special items, was $0.22 and ahead of our expectations.
In terms of specific numbers, we expect the following: for the third quarter, revenue of $1.3 billion, plus or minus $20 million; EBITDA of $295 million, plus or minus $10 million; EBITDA margin of 22.7%, plus or minus 40 basis points; and earnings per share of $0.25, plus or minus $0.02.
And for the year, we expect revenue to be $5.1 billion, plus or minus $50 million; EBITDA baseline to increase to $1.17 billion, plus or minus -- plus $15 million, minus $25 million; EBITDA margin to increase to 22.9%, plus 10 basis points and minus 20 basis points; earnings per share increase to $0.99, plus or minus $0.03; cash flow baseline increase to $450 million, plus or minus $35 million.