Joel Reiss
Co-Chief Operating Officer at TransDigm Group
Good morning. I'll start with our typical review of results by key market category. For the remainder of the call, I'll provide commentary on a pro-forma basis compared to the prior year period in 2024. That is assuming we own the same mix of businesses in both periods. The market discussion includes the 2024 acquisitions in both periods.
In the commercial market, which typically makes up close to 65% of our revenue, we will split our discussion into OEM and aftermarket. Our total commercial OEM revenue decreased approximately 4% in Q1 compared with the prior year period.
Commercial transport OEM, this is largely Boeing and Airbus, was down 1%. Biz jet and helicopter OEM revenue was down 8%. Sequentially, total commercial OEM revenues contracted by 17% in Q1. Bookings in the quarter were solid, up both sequentially and against prior year Q1.
Our commercial OEM business was impacted in the quarter by the Boeing machine strike, which affected its 737 MAX, 767 and 777 production lines. In total, the strike and subsequent production restart lasted roughly 12 weeks, specific to TransDigm since we shipped to rent as well as through sub-tiers on the effective platforms, the impact across our businesses is uneven and varied.
Boeing's receiving docks were closed during the strike, while some sub-tiers continue to drive consistent demand. This will likely cause further commercial OEM impact into the balance of the year. It is too soon to determine how much of an impact the strike will have in what is a fragile supply-chain recovery. Precisely predicting the ramp-up and the flow-through to the supply-chain is tough. However, the commercial OEM guidance we are reiterating today contains what we believe is an appropriate level of risk around the 737 MAX, 767 and 777 production build rates for the 2025 fiscal year.
As we noted on our last earnings call, shortly after the strike began, we proactively initiated cost-reduction initiatives across our operating units to right size our structure to account for the lower 2025 OEM production environment. These cost-reduction initiatives span furloughs, headcount reduction, hiring freezes, acceleration of productivity projects and a range of other actions aimed at reducing expenses. These initiatives enable us to beat our Q1 and active productivity target and put us in a good position for the year.
In addition, as-is typical for us, we will add resources judiciously as we see the higher ramp rate materialize. The business jet helicopter miss in-quarter one versus prior year is primarily timing-related, but we were also impacted by the four-week Textron strike. Bookings were up nicely in Q1 over the same-period last year, which should set us up for growth in the balance of the year.
Now moving on to our commercial aftermarket business discussion. Total commercial aftermarket revenue increased by approximately 9% compared with the prior year period. Sequentially, total commercial aftermarket revenues grew by about 4% compared to Q4 '24.
Commercial aftermarket bookings were solid compared to prior year. Bookings and shipments are running in-line with our expectations and continue to support our unchanged 2025 commercial aftermarket guidance of high-single-digit to low double-digit revenue growth.
As a reminder, and as we've said many times before, the commercial aftermarket can be lumpy and when forecasting our commercial aftermarket, we always focus on 12-month trends, not quarterly trends.
Our commercial aftermarket is made-up of four submarkets, passenger, interior, freight and business yet. This quarter, the growth across the four submarkets was varied, but not significantly disconnected from what we had anticipated. All four submarkets revenue increased versus Q1 of last year.
Business jet was stronger and freight weaker than the total commercial aftermarket 9% growth rate. The passenger submarket performed in-line with the overall commercial aftermarket rate of growth. Within our passenger segment, operating units with higher engine content posted very solid growth, well in excess of those with non-engine content.
Additionally, quarter one point-of-sales data from our distribution partners increased well into double-digits versus quarter one of last year. These factors give us confidence we will achieve the commercial aftermarket growth rate guidance for fiscal 2025.
Turning to broader market dynamics and referencing the most recent traffic data for December. Global revenue passenger miles have continued to surpass pre-pandemic levels since February of 2024. 2024 air traffic increased 10.4% above 2023 and is about 3.8% above pre-pandemic levels.
Our PKs in December were up 8.6% versus prior year, while ASKs were up 5.6% as passenger load factor is at near-record highs of 84%, driving the additional upside. IATA currently expects traffic to reach 113% of 2019 levels in 2025 and to surpass prior year traffic by 8%. Domestic travel also continues to surpass pre-pandemic levels.
In the most recently reported traffic data, global domestic air traffic was up 5.7% compared to 2023 and 9.7% compared to 2019. Domestic air travel growth has been driven significantly by outsized growth in China where air travel was up 20.2% compared to 2019.
International traffic continues to trend upwards and has been above pre-pandemic levels for the past few months. In the most recently reported data for 2024, international travel was about 0.5% above 2019 levels. Most international markets saw stable-growth with Asia-Pacific, the major driver of the increase.
Shifting to our defense market, which is traditionally is at or below 35% of our total revenue. The defense market revenue, which includes both OEM and aftermarket revenues grew by approximately 11% compared with the prior year period. Q1 defense revenue growth was well distributed across our businesses and customer-base. We saw similar growth in both the OEM and aftermarket components of our total defense market with the aftermarket running slightly ahead of OEM.
Defense bookings for the quarter were healthy compared to the prior year and continue to support our unchanged 2025 defense guidance of high single-digit revenue growth. However, as you know, defense sales and bookings can be lumpy and forecasting them with precision on a quarterly basis is difficult, similar to my commercial aftermarket commentary, the defense growth rates could also be uneven over the individual quarters of 2025.
In addition, we continue to see steady improvements in on-time delivery and other key customer performance metrics, which are now approaching 2019 levels. With improving supply-chain performance, we are on-track to surpass those levels later this year. We also saw good new business awards and bookings in the quarter in both commercial and defense markets. Corey Electronics was selected by a major OEM as the provider of a flight deck control panel systems for a new derivative platform.
As the incumbent on other platforms with this customer, Cory was well-positioned to be responsive to their timeline, providing the right technology, customization and capability required in an exceptionally short period of time. In addition to Corey Electronics, we had solid awards during the quarter at Airborne Systems North-America, Armtec, Calspan and Chelton Limited within the quarter.
During the quarter, we saw our succession planning at-work with one executive for an EVP Retirement and two EVP promotions. Pete Palmer, after an impressive 25-year career with TransDigm has retired. Pete began as a product-line manager at AdelWiggins and evolved into a key leader within our organization. His contribution span multiple areas, including mergers and acquisitions, serving as President of several business units, playing a pivotal role in the Esterline integration and spearheading our TransDigm University leadership development program in partnership with the University of Southern California. We extend our heartfelt thanks to Pete for his dedication and wish him a well-deserved relaxing retirement.
With Pete's retirement and the acquisitions made in 2024, we promoted two accomplished leaders to Executive Vice-President Roles. Jason Marlett, who joined us in 2008, has accumulated 17 years of experience across several TransDigm operating units. His most recent role was as President of Champion Aerospace and Liberty South Carolina. Jason was promoted in October and now will oversee six operating units.
Similarly, Chris Blackford, who has served with TransDigm for 11 years was promoted in November. Chris has held leadership roles across multiple units, including his most recent position as President of Airborne Systems, North-America. Like Jason, Chris will be responsible for overseeing six operating units. We are confident that both Jason and Chris will continue driving operational excellence and value-creation across the organization.
Lastly, I'd like to wrap-up by expressing how pleased I am by our operational performance in the first-quarter. It was a very good start to our fiscal 2025. As we progress further into fiscal '25, our management teams remain focused on our consistent operating strategy and servicing the strong demand for our products.
With that, I would like to turn it over to our Chief Financial Officer, Sarah Wynne.
