Regional Jets Explained: Embraer, CRJ, and ATR Compared

What Is a Regional Jet?

Regional jets are small commercial aircraft designed to connect smaller cities to major hub airports, operating routes that are too short or too thin to justify larger mainline aircraft. Unlike turboprops — which use propeller engines driven by gas turbines — regional jets use conventional turbofan jet engines, offering higher speeds, greater passenger comfort, and improved performance at altitude. They typically seat between 37 and 100 passengers, fly routes of 200 to 1,500 miles, and operate at altitudes and speeds comparable to larger mainline jets.

The regional jet transformed the economics of connecting smaller communities to the global aviation network. Before regional jets, connecting a city of 200,000 people to a hub 400 miles away often meant choosing between turboprops (slower, noisier, prone to weather delays) or accepting low-frequency service with mainline jets operating at poor load factors. Regional jets bridged this gap: they are fast enough to compete with driving on distances up to 400 miles, economical enough to operate at the load factors achievable on thin routes, and comfortable enough that business travelers — the highest-yielding passenger segment — are willing to use them.

The two dominant regional jet manufacturers are Embraer of Brazil and Bombardier of Canada (whose commercial aircraft division was acquired by Mitsubishi in 2020 and is now branded as MHI RJ Aviation Group). Their primary competing families are the Embraer ERJ and E-Jet families and the Bombardier/Mitsubishi CRJ (Canadair Regional Jet) family. These two manufacturers have sold thousands of aircraft to regional carriers worldwide and have largely defined the modern regional aviation market.

Embraer's regional jet families span a wide range. The older ERJ family — ERJ-135 (37 seats), ERJ-140 (44 seats), and ERJ-145 (50 seats) — entered service in the late 1990s and remains operational at numerous carriers worldwide. The newer E-Jet family — E170, E175, E190, and E195 — entered service from 2004 and seats 70 to 122 passengers. The E175 in particular became the most commercially significant regional jet in the US market due to its specific fit within scope clause limits.

The CRJ family follows a similar size progression: the CRJ-200 (50 seats), CRJ-700 (70 seats), CRJ-900 (76-90 seats), and CRJ-1000 (100 seats). The CRJ-200 was ubiquitous in US regional aviation during the 2000s; at one point, there were more than 1,000 CRJ-200s operating across North America. Production of the CRJ family ended in 2020 following Mitsubishi's acquisition, making it an orphaned product line dependent on existing parts and maintenance support.

Scope Clauses: The Rules That Define Regional Aviation

No concept is more important to understanding US regional aviation than the scope clause. These are contractual provisions within pilot collective bargaining agreements between major airlines and their pilot unions — specifically ALPA (Air Line Pilots Association) — that restrict how many regional jets can be operated, what size those jets can be, and under what conditions they can fly.

Scope clauses exist because mainline pilots view regional jets as a competitive threat to their jobs. If a major airline can replace a 150-seat mainline jet route with three 50-seat regional jet routes, operated by pilots earning dramatically lower wages at the regional affiliate, the mainline pilot workforce loses work. Scope clauses are the contractual mechanism through which mainline pilots have historically limited this substitution.

The most consequential scope clause restriction in the US market is the 76-seat limit. For many years, Delta, United, and American were prohibited by their pilot contracts from having regional affiliates operate aircraft with more than 76 seats. This single provision is the reason the Embraer E175 (configured to 76 seats rather than its maximum 80) became by far the most common new regional jet purchased in the US during the 2010s and early 2020s. Airlines wanted larger regional jets — 80, 90, or 100 seats — but were blocked by scope. The E175 at exactly 76 seats was the maximum allowed.

Scope clauses also typically limit the total number of regional aircraft an airline can operate. United Airlines, for example, has been limited to a specific number of regional jet departures as a percentage of total system departures. These numerical limits create ongoing tension between mainline carriers (who want more flexibility to operate regional jets on marginal routes) and mainline pilot unions (who want to protect the scope of mainline flying).

As labor shortages reduced the regional pilot supply in the post-COVID period, scope clause negotiations shifted somewhat. Regional carriers struggled to staff their aircraft, creating pressure to relax restrictions — not because mainline pilots had become more accommodating but because the practical alternative was simply not flying those routes at all. Some renegotiations occurred, and discussions about expanding scope to 90-seat aircraft became more serious as the staffing crisis made smaller regional jets economically marginal to operate.

The Economics of Regional Operations

Regional airlines operate under two primary business models: the traditional independent model and the capacity purchase agreement (CPA) model, also called the code-share or feed model. The CPA model now dominates US regional aviation and has fundamentally changed the economics and risk profile of operating regional jets.

Under a capacity purchase agreement, the major airline (called the "mainline partner" or "brand partner") pays the regional carrier a fixed rate to operate flights on its behalf. The regional carrier flies under the major airline's brand, using its livery, code, and customer-facing identity — hence airline names like "United Express," "Delta Connection," and "American Eagle" are actually operated by independent regional carriers including SkyWest Airlines, Endeavor Air, Mesa Air, and others. The major airline collects all passenger revenue and handles all ticket sales and marketing. The regional carrier simply executes the flying.

This model transfers virtually all revenue risk from the regional carrier to the major airline. Whether seats are full or empty, the regional carrier receives its contracted rate per flight. This creates stable, predictable revenue — attractive to regional carriers that lack the network scale and brand power to compete in the open market. It also allows major airlines to expand their regional network at relatively low risk, since they are not committed to specific aircraft but rather to specific routes operated by contracted partners.

However, CPAs are increasingly expensive to negotiate and maintain. As the regional pilot shortage drove up wages at regional carriers, the contracted rates airlines paid had to increase substantially. United Airlines' payments to regional partners increased dramatically from 2021 to 2024, reflecting both higher pilot costs and the competitive market for aircraft leases. These cost pressures made some regional routes economically unviable under CPA structures, leading to route suspensions and airport communities losing air service.

Regional carrier consolidation has been a defining trend of the past two decades. The US regional airline industry has shrunk from more than 50 carriers in 2000 to fewer than 10 significant operators by 2025. SkyWest Airlines is the dominant survivor, having outlasted competitors through superior operational performance, conservative balance sheet management, and diversified partnerships across multiple major airlines. Envoy Air (formerly American Eagle), wholly owned by American Airlines, is the second largest. The attrition of smaller regional carriers reflects the difficulty of the business model: thin margins, labor-intensive operations, and dependency on major airline partners who can terminate or renegotiate contracts.

Embraer vs. CRJ: A Technical Comparison

The Embraer E-Jet family and the Bombardier CRJ family competed intensely for regional jet orders through the 2000s and 2010s, with each manufacturer claiming technical and commercial advantages. The competition illuminated meaningful differences in aircraft design philosophy and operational characteristics.

The most fundamental difference is fuselage cross-section and passenger experience. The CRJ-700 and CRJ-900 use a narrow fuselage originally designed for the 50-seat CRJ-200, resulting in a 2-1 seat configuration with overhead bins too small for standard roller bags in many configurations. Passengers must gate-check bags on most CRJ flights. The Embraer E175 uses a significantly wider fuselage with a 2-2 seat configuration and overhead bins large enough for carry-on bags — a substantially superior passenger experience. Airlines operating both types consistently report higher passenger satisfaction scores on E-Jet flights.

The operational economics have been more competitive. The CRJ family benefits from lower acquisition costs and well-established maintenance networks built over decades. Operators with large existing CRJ fleets have invested in type ratings, tooling, and spare parts — sunk costs that make switching to Embraer expensive even when the Embraer product is superior on paper. SkyWest operates one of the largest CRJ fleets in the world alongside its E175 fleet, reflecting these mixed fleet economics.

The E175-E2, Embraer's next-generation regional jet, promised substantially improved fuel economy through new Pratt and Whitney GTF engines, a new wing, and aerodynamic refinements. However, the E175-E2 has found limited adoption in the US precisely because its specifications push it into a gray area relative to scope clause limits — its MTOWs and other characteristics make its classification ambiguous. The standard E175 (E1 generation) remains the dominant US regional jet for new deliveries despite being a design that entered service in 2004.

The Future of Regional Aviation

The regional jet market faces its most significant structural challenge in decades. A combination of pilot shortages, aging fleets, changing scope clause dynamics, and the emergence of new aircraft categories is forcing a fundamental reassessment of how regional aviation works.

The post-COVID pilot shortage hit regional carriers hardest. First officers at regional carriers in the US have historically earned wages significantly below mainline carriers, creating a natural career progression where pilots build hours in regional jets before applying to mainlines. When major airlines accelerated hiring to address their own post-pandemic staffing needs, the pipeline of experienced regional first officers thinned rapidly. Regional carriers responded with dramatic pay increases — some regional first officers now earn salaries that would have been unthinkable at regional carriers five years ago — but the supply of qualified candidates (who must meet the 1,500-hour Air Carrier qualification requirement) remains constrained.

The 50-seat regional jet era appears to be ending. The CRJ-200 and ERJ-145, the dominant 50-seat platforms of the 2000s, are expensive to operate relative to their passenger yield given their age, fuel consumption, and maintenance costs. As experienced crews age out and new pilots gravitate toward better-paying opportunities, 50-seat operations become increasingly difficult to staff and economically justify. The communities that depend on 50-seat service to hub connections are particularly vulnerable.

The ATR 72 and Dash 8 turboprops are seeing renewed interest for routes that cannot justify jet operations economically. Modern turboprops offer fuel efficiency advantages on shorter routes where the speed penalty is less significant, and they are well-suited to airports with shorter runways. Cape Air, Silver Airways, and several Canadian carriers have built networks around turboprop operations to communities that regional jets cannot serve economically.

Electric and hybrid-electric propulsion represents the medium-term technology frontier for regional aviation. Startups including Heart Aerospace, Eviation, and established manufacturer ATR have announced electric or hybrid regional aircraft programs targeting 30-to-80-seat capacity and range of 200-to-400 miles. These aircraft are not commercially available as of 2025, but certification timelines suggest entry into service is possible in the late 2020s to early 2030s. Their economic case depends heavily on electricity costs at regional airports and the charging infrastructure investment required — a significant additional hurdle for the airports most in need of improved connectivity.

Essential Air Service and Community Connectivity

The fate of regional aviation is closely linked to the Essential Air Service (EAS) program — the federal subsidy program established by the Airline Deregulation Act of 1978 to ensure that communities that had been served by regulated airlines continued to receive at least minimal air service after deregulation removed the mandate to serve them commercially. EAS currently subsidizes service to approximately 175 communities in the United States, providing federal payments to carriers willing to operate service on routes that would otherwise be commercially unviable.

The program costs approximately $350-400 million per year and serves communities primarily in the rural West, Alaska, and parts of the Midwest and South where driving distances to the nearest large airport would otherwise be prohibitive. Carriers including Cape Air, PenAir, and various regional operators compete for EAS contracts, often operating turboprops rather than regional jets on the thinnest routes. EAS serves an important social function — connecting rural communities to the national air travel network — but its economics are fragile. As operating costs have risen and the pool of qualified pilots at regional carriers has thinned, some EAS contractors have exited contracts mid-term, forcing the Department of Transportation to find replacement carriers at sometimes significantly higher subsidy rates.

Alaska occupies a uniquely important place in the regional aviation story. With vast distances, minimal road infrastructure, and communities accessible only by air, Alaska has the highest per-capita air travel volume of any US state and depends on regional aviation in ways that no other state does. Bush operators including Ravn Alaska, PenAir, and Bering Air connect scores of villages and remote communities to larger hubs using a diverse mix of aircraft including Cessna Caravans, Beechcraft King Airs, and various twin-engine piston aircraft. The Alaska aviation ecosystem operates under conditions — extreme cold, unprepared landing strips, high weather variability — that are completely unlike the controlled conditions of continental regional aviation, and it has developed distinctive operational expertise and aircraft modification knowledge as a result.