Bell 214ST: 165 mph Super Transport Helicopter & Iranian Military Origin
Bell 214ST – The "Super Transport" medium-lift helicopter, engineered for 165 mph speed and 8,000 lb external load capability.
The Bell 214ST is a unique chapter in helicopter history—a design born from a massive Iranian military order that was never fulfilled, yet went on to become a respected medium-lift helicopter in both civilian and military service. Developed by Bell Helicopter as a twin-engine evolution of the single-engine Bell 214, the "ST" originally stood for "Stretched Twin" and later "Super Transport." With a top speed of 165 mph (143 knots / 264 km/h) and an external load capacity of 8,000 lbs (3,630 kg), the 214ST filled a niche for a medium-lift helicopter that could operate in hot-and-high conditions. This is the complete engineering breakdown of Bell's "Super Transport."
1. Aerospace Overview
The Bell 214ST is a medium-lift, twin-engine helicopter developed by Bell Helicopter in the late 1970s. Originally conceived as a military project funded by the Iranian government, the 214ST was designed to meet Iran's requirement for a large, twin-engine helicopter capable of operating in the country's hot and high conditions. The program was based on the Bell 214B BigLifter, but with a stretched fuselage, twin General Electric CT7 engines, and a host of other improvements. When the Iranian Revolution in 1979 canceled the order, Bell decided to continue development as a commercial venture, aiming at the offshore oil industry and utility market. First flown in February 1977, the 214ST received FAA and CAA certification in 1982 and was produced until 1993, with a total of 96 aircraft built. Unlike the Sikorsky S-92 which dominates the modern offshore market, the 214ST was a product of its era—rugged, simple, and effective, but ultimately produced in limited numbers.
2. Top Speed & Velocity Profile
| Metric | Value (214ST) |
|---|---|
| Maximum Speed | 143 knots (165 mph / 264 km/h) |
| Cruise Speed | 140 knots (161 mph / 259 km/h) |
| Rate of Climb | 1,780 ft/min (9.04 m/s) |
| Service Ceiling | 10,400 ft (3,170 m) |
| Range (internal fuel) | 435 nautical miles (500 miles / 805 km) |
| Hover Ceiling (IGE) | 10,400 ft (3,170 m) |
3. Rotor System & Aerodynamics
The 214ST's rotor system was a significant advancement over earlier Bell designs, introducing composite blades and elastomeric bearings for reduced maintenance.
- Main Rotor: Two-blade, fully articulated, with composite blades
- Rotor Diameter: 52 ft (15.85 m)
- Blade Design: Fiberglass composite blades, 26 ft long with 2.75 ft chord—among the largest composite blades on any helicopter at the time
- Tail Rotor: Two-blade, 9 ft 10 in (3.0 m) diameter
- Rotor Hub: Elastomeric bearings (no lubrication required)
- Transmission: One-hour run-dry capability—a groundbreaking safety feature
4. Propulsion System
The 214ST was powered by two General Electric CT7-2A turboshafts, a derivative of the T700 engine family that powers the Black Hawk and Apache.
- Engines: Two General Electric CT7-2A
- Type: Turboshaft with axial-centrifugal compressor
- Takeoff Power (each): 1,625 shp (1,212 kW)
- Total Power Available: 3,250 shp (2,424 kW)
- Transmission Rating: 3,000 shp (2,240 kW) continuous
- Fuel Capacity: 435 US gallons (1,650 L) internal
- Fuel System: Single-point pressure refueling for rapid turnaround
5. Airframe & Structures
The 214ST's airframe was derived from the Bell 205/212 family but stretched by approximately 3 ft to create a larger cabin.
- Length (fuselage): 49 ft 4 in (15.03 m)
- Length (rotors turning): 62 ft 2 in (18.95 m)
- Height: 15 ft 11 in (4.84 m)
- Cabin Dimensions: Approximately 262 cu ft (7.4 m³) cabin volume
- Empty Weight: 9,481 lbs (4,300 kg)
- Maximum Takeoff Weight: 17,500 lbs (7,938 kg)
- External Load Capacity: 8,000 lbs (3,630 kg) on cargo hook
- Landing Gear: Available as skids or wheels; wheeled gear developed to reduce rotor downwash issues during hover taxi
6. Cabin & Configurations
The 214ST's stretched cabin made it versatile for both passenger and cargo missions.
- Passenger Configuration: Up to 18 passengers in high-density seating
- Crew: 2 pilots
- Cargo Configuration: Flat floor with tie-down points
- Doors: Two large sliding doors for easy loading
- Cockpit Door: Separate cockpit door for crew access
- Internal Baggage: 40 cu ft (1.1 m³)
- External Baggage: 65 cu ft (1.8 m³)
⚙️ TECH INSIGHT: The Iranian Connection
The Bell 214ST's origin story is one of the most unusual in helicopter development. In the 1970s, Iran was a major customer for Bell helicopters, operating hundreds of Bell 214A/C and AH-1J SeaCobra models. The Imperial Iranian Armed Forces funded the development of a twin-engine version of the Bell 214, specifically designed for their requirements—including the ability to operate in hot and high conditions and to carry significant payloads. The plan was massive: Iran intended to build 350 Bell 214STs at a new production plant in Isfahan, with technical assistance from Bell and Textron. The prototype first flew in February 1977, and work started on three conforming prototypes in 1978. But the Iranian Revolution in 1979 changed everything. The Shah was overthrown, the new government canceled all military contracts, and Bell was left with a fully developed helicopter and no customer. Rather than abandon the project, Bell pivoted to the civilian market, targeting the offshore oil industry. The "ST" designation was originally "Stretched Twin," but was later rebranded as "Super Transport" to appeal to commercial operators. This twist of history explains why the 214ST exists—it was a helicopter designed for a military customer that never was, but found a second life in the civilian world. Of the 96 aircraft built, many served with offshore operators like Bristow and British Caledonian, and several found military homes with countries like Iraq, Peru, and Thailand.
7. Operational History
Despite its limited production run of 96 aircraft, the 214ST served with a variety of operators worldwide.
- Military Operators: Peruvian Air Force (11), Royal Thai Navy (9), Iraqi Air Force (48, now retired), Venezuelan Air Force (4, retired), Royal Brunei Air Force (1)
- Civil Operators: Bristow Helicopters (UK), British Caledonian Helicopters, CHC Helicopter (Canada/US/Norway), Helicopter Transport Services
- Notable Service: Iraqi 214STs were used for rapid troop transport and casualty evacuation during the Iran-Iraq War
- Gulf War: Several Iraqi 214STs were captured by US forces during Operation Desert Storm and some were flown by US civilian operators afterward
- Current Status: Production ended in 1993; approximately 30 remain in commercial service
8. Aerospace Speed Classification
According to the Speedo Science Aerospace Index, the Bell 214ST occupies the Low Subsonic class, typical for medium-lift helicopters of its era.
| Class | Speed Range | Example Aircraft |
|---|---|---|
| Hypersonic | Mach 5+ | X-43, X-51, SR-72 (planned) |
| Supersonic | Mach 1.0–5.0 | F-35A, SR-71, F-22, Concorde |
| High Subsonic | Mach 0.7–0.99 | B-2, RQ-180, X-47B, T-45 |
| Low Subsonic | | Bell 214ST, S-92, V-22, CH-53E, Bell 429, AH-1 Cobra | |
9. Technical Specifications
| Specification | Data (Bell 214ST) |
|---|---|
| Manufacturer | Bell Helicopter (Bell Textron) |
| Type | Medium-lift transport helicopter |
| Length (fuselage) | 49 ft 4 in (15.03 m) |
| Length (rotors turning) | 62 ft 2 in (18.95 m) |
| Height | 15 ft 11 in (4.84 m) |
| Main Rotor Diameter | 52 ft (15.85 m) |
| Tail Rotor Diameter | 9 ft 8 in (2.95 m) |
| Cabin Volume | 262 cu ft (7.4 m³) |
| Empty Weight | 9,481 lbs (4,300 kg) |
| Maximum Takeoff Weight | 17,500 lbs (7,938 kg) |
| External Load Capacity | 8,000 lbs (3,630 kg) |
| Engines | 2 × General Electric CT7-2A |
| Engine Power (each) | 1,625 shp (1,212 kW) |
| Total Power Available | 3,250 shp (2,424 kW) |
| Maximum Speed | 143 knots (165 mph / 264 km/h) |
| Cruise Speed | 140 knots (161 mph / 259 km/h) |
| Rate of Climb | 1,780 ft/min (9.04 m/s) |
| Service Ceiling | 10,400 ft (3,170 m) |
| Range | 435 nm (500 miles / 805 km) |
| Hover Ceiling (IGE) | 10,400 ft (3,170 m) |
| Fuel Capacity | 435 US gallons (1,650 L) |
| Passenger Capacity | 16-18 passengers |
| Crew | 2 pilots |
| First Flight | February 1977 |
| Introduction | 1982 |
| Production Years | 1979–1993 |
| Number Built | 96 |
10. Velocity Engineering Insight
At 165 mph (143 knots), the Bell 214ST's kinetic energy at MTOW is approximately 18 megajoules—comparable to the Bell 429 but in a much larger, more utilitarian airframe. However, the 214ST's true engineering achievement is not speed but versatility—the ability to carry 8,000 lbs externally or 18 passengers internally, all while operating from unprepared sites or ships at sea.
The two-blade rotor system, while seemingly antiquated compared to modern four-blade or five-blade rotors, offered significant advantages in simplicity and maintenance. The composite blades were a major advance—lighter, more durable, and corrosion-resistant compared to metal blades. The elastomeric rotor hub bearings eliminated the need for daily lubrication, reducing maintenance hours dramatically.
The one-hour run-dry transmission capability was groundbreaking in 1982. If the transmission lost oil pressure, it could continue operating for a full hour, giving the crew time to fly to a safe landing site. This feature, derived from military requirements, was virtually unheard of in civilian helicopters at the time and demonstrates the 214ST's heritage as a design intended for military use.
According to the Speedo Science Aerospace Index, the 214ST's 165 mph top speed places it in the Low Subsonic class alongside other medium-lift helicopters, but its unique origin story sets it apart. It was a helicopter designed for one customer, built for another, and ultimately found homes around the world—a true orphan that became a workhorse.
11. Conclusion
The Bell 214ST is a fascinating footnote in helicopter history—a design born from a massive military contract that never materialized, yet still managed to find its place in the world. Its 165 mph speed, 8,000 lb external load capacity, and 18-passenger cabin made it a capable medium-lift helicopter for its era.
In the Speedo Science Aerospace Index, the 214ST occupies the Low Subsonic class alongside other rotorcraft like the Sikorsky S-92 and Bell 429, but its story is unique. While the S-92 dominates the modern offshore market and the Bell 429 serves corporate clients, the 214ST was a bridge between generations—combining Bell's proven two-blade rotor technology with modern composite blades and twin-engine reliability.
For engineers, the 214ST demonstrates that sometimes the most interesting aircraft come from unexpected origins. The Iranian-funded development, the pivot to commercial markets, and the eventual military service with countries like Iraq and Peru all contributed to a rich operational history that few helicopters can match.
With only 96 built, the 214ST is a rare sight today, but its legacy lives on in the lessons learned about composite blades, run-dry transmissions, and the importance of designing for hot-and-high conditions—lessons that influenced later designs like the S-92 and V-22 Osprey.
📌 RELATED AEROSPACE ARTICLES
→ Sikorsky S-92: 155 knots Offshore Helicopter & HUMS Predictive Maintenance →
→ Bell 429 GlobalRanger: 178 mph Light Twin Helicopter →
→ Sikorsky CH-53E Super Stallion: 196 mph Heavy-Lift Helicopter →
Source: Bell Helicopter | Flight International | Vertical Flight Society | Iranian Revolution Archives | Speedo Science Database
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