Product Comparison. 480B vs. Robinson R44

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1 Product Comparison 480B vs. Robinson R44

2 480B vs. Robinson R44 Specifications Enstrom 480B Robinson R44 Seats 1/4 or 2/1 1/3 Continuous Engine Power (To Drivetrain) 277 shp/206 kw 205 shp/183 kw Gross Weight 3000 lbs/1361 kg 2500 lbs/1134 kg Empty Weight (As Configured) 1820 lbs/826 kg 1511 lbs/684 kg Payload (As Configured) 1180 lbs/535 kg 989 lbs/448 kg Maximum Cruise Speed 115 kts/213 kmh 117 kts/216 kmh Range (internal fuel) 380 nm/704 km 348 nm/645 km Maximum Takeoff Weight 3000 lbs/1361 kg 2500 lbs/1134 kg Service Ceiling Gross Weight = 2,850 lbs Gross Weight = 2500 lbs RHI numbers, actual numbers may be higher ft 3962 m ft 4267 m Hover Ceiling IGE ft/3865 m 8950 ft/2812m Hover Ceiling OGE 5400 ft/1696 m 4500 ft/1413 m (max gr. wt.) Rate Of Climb 1600 fpm 1000 fpm 8.1 m/s 5 m/s Main Rotor Diameter 32 ft/9.8 m 33 ft/10.1 m Number Of Rotor Blades 3 2 DOC (US dollars) $ $ Standard fuel capacity 90 gal/341 lit 30.6 gal/116 lit Vne 125 kts/232 km 120 kts/223 km

3 480B vs. Robinson R44 Cockpit Comparison The 480B offers an easily reconfigurable seating arrangement that is unique to the industry. The controls are removable simply by pulling pins, and the seats can either be removed or folded up. The cabin can be configured with seating for up to five people, a medivac stretcher with an attendant, or a flat cargo floor. All this can be accomplished in only minutes, without the use of tools. Both the pilot and co-pilot s seats are fully adjustable, along with adjustable rudder pedals, making the 480B comfortable for pilots of any stature. This feature, along with a NASA developed seat foam, make the 480B comfortable to fly for extended periods of time, and reduce pilot fatigue. The extra wide cabin of the 480B creates ample shoulder and leg room for pilots and passengers alike. All occupants enjoy near unrestricted visibility as well. R44 Cockpit Size vs 480B (shaded) The seating in the R44 is not adjustable or flexible, meaning that non-average size pilots often have to stack or remove cushions in order to reach the flight controls. In the two rear seats of the R44 leg room and visibility are limited by the front seats. Additionally, all baggage in the R44 must be stored in the main cabin, usually under the seats. This drastically limits the amount of space inside the helicopter, and effectively limits it to a three place (or less) aircraft when baggage is carried. Conversely, the 480B has a large baggage compartment located in the back of the fuselage, freeing up cabin space.

4 480B vs. Robinson R44 Performance and Flying Qualities Performance and flight characteristics are two of the most important issues when looking at any helicopter. The 480B has a heavy, fully articulated, three-bladed rotor system, while the R44 only has a lightweight, twobladed, teetering rotor system. The 480B rotor system is very high inertia, providing much better performance during an autorotation than the lighter weight R44. In the 480B reaction time to a loss of power is less critical than in a R44. The 3-bladed rotor also has a lower disc loading, meaning it can recover more easily from a loss of energy. A 3-bladed rotor generally will perform better in low-g maneuvers, or in high load situations such as high density altitude, wind gusts, or high airspeed. The R44 s 2-bladed rotor head has a potential for mast bumping, while the 480B s 3-bladed fully articulated design will not mast bump. Because of the different styles of rotor system, the aircraft must be flown different. The R44 s low inertia rotor system and resultant H/V chart require that approaches start from a high altitude and/or be made at a high airspeed. Conversely, with its high inertia rotor system, the 480B has a relatively forgiving H/V chart and approaches can be made at lower speeds. Finally, the R44 has been known to suffer from loss of tail rotor effectiveness (LTE). With its large, unblocked tail rotor the 480B has no LTE issues and can perform hot, high, and heavy out of ground effect hovers, as well as take off, taxi, and fly in high winds from any direction. The R44 uses hydraulic controls, mainly in order to reduce stick force requirements and damp out unwanted vibrations. The 480B uses direct mechanical controls with electric trim. The mechanical controls are simpler than hydraulics, are less failure prone, and require less maintenance. In addition they provide more feedback and response to the pilot, making the aircraft easier and more enjoyable to fly. The 480B has matched/tabbed blades and balanced rotating components to eliminate unwanted vibrations. Finally, the R44 uses a unique T-bar cyclic that shares a single control between two pilots. Many pilots find this disconcerting. The 480B uses two much more standard floor mounted cyclics that are familiar and comfortable to a majority of pilots. 480B H/V Chart R44 H/V Chart

5 480B Mast and Internal Control System Enstrom is known for a unique dynamic control system which many times catches the attention of prospective buyers. Approaching the design with a clean sheet of paper, the original Enstrom designers decided to make an aircraft that had all the strength and durability that every helicopter owner would want, and a rotor control system that was protected from the environment as much as possible. Hence, the supremely successful internal control rod system of Enstrom was born. The first thing that people notice is that the typical swashplate and mechanical linkages are not directly under the rotor head of the helicopter. This, often times, leads to a false impression that the mast is somehow less stout, or that the Enstrom has a skinny mast. This perception comes about mainly because the mast isn t shrouded or blocked by external controls and swashplates. In reality the Enstrom mast is larger than most other helicopters it s size. For example, as seen from the photo to the rigth, the 480B mast is significantly larger than the Bell 206BIII mast. The manner in which the control system works actually necessitates a larger diameter rotor mast for the 480B. Three pitch control rods are connected to the swashplate below the transmission, and they run through the rotor mast up to the top of the rotor head where they connect to walking beams and pitch change links that control the pitch of the rotor blades. With this design, the swashplate and control rods are almost completely out of the elements and protected. Another side benefit of this design is that there are no mechanical linkages or plates that could be damaged due to debris from outside of the aircraft. Even kite string has been known to entangled with the outside control mechanical systems and bring down other aircraft. This isn t a problem on the 480B.

6 480B vs. Robinson R44 Maintenance and Servicing A major difference between the 480B and the R44 is in maintenance philosophy. The R44 life limits each component and the entire helicopter to 12 years or 2200 hours, whichever comes first. Once one of those limits is reached, the aircraft must be returned (at the owner s expense) to one of a small number of overhaul centers, or the Robinson factory for a comprehensive overhaul. This overhaul is often more than 50% of the purchase price of the original helicopter. Robinson will not allow a standard commercial field maintenance organization or mechanic to do anything other than routine, basic service to their helicopters. Enstrom has an almost exact opposite maintenance philosophy. There are only 9 life limited parts on the 480B. Everything else, including rotor blades, is replaced on an on-condition basis. Transmission overhauls are available on an exchange basis so that the parts can be changed out in the field with a minimum of downtime. There is no life limit on the 480B airframe. The 480B can be almost fully serviced by any competent maintenance organization or licensed mechanic. Additionally, each aircraft sold comes with a free maintenance course for the owner s mechanic taught at the factory. Finally, the 480B uses a lightweight, state of the art Rolls Royce 250-C20W turbine engine. The R44 uses a heavy Lycoming IO-540 piston engine. In addition to being more powerful (especially at high altitude since the R44 is naturally aspirated), the 480B s turbine engine requires less maintenance, and uses much more readily available jet fuel. Additionally, the 480B can run on a number of alternative fuels in an emergency. The R44 requires 100 octane leaded avgas only, which can often be difficult to find, or expensive. Blades in production at the Enstrom facility Enstrom 480B RR 250-C20W Robinson R44 Lycoming IO-540