Business Aviation

Learjet 45 did not meet the promises of developers and customers fell short of expectations primarily because during the development of overweight , thus virtually denying operators the ability to install optional equipment , often vital . Bombardier intended to keep operating weight below 5.5 tonnes and the price - below $ 6 million , so the list of optional equipment were FMS, GPS, TCAS, GPWS and ELT. " Overboard " and were such important things like in-flight entertainment system (IFE), telephony and even APU . Weight APU with strapping - under 100 kg. As a result, the average weight increased by Learjet 45 ton or more , leaving behind advertised Bombardier operating weight .

Post-Certification Several modifications were designed to improve the situation. Thus, increased payload with full fuel tanks , but to the detriment of the landing characteristics : take-off distance increased from 1280 to 1600 m

Do Learjet 75 LTH better mainly due to the increase of the available traction at 140 kg , which provided a welcome reduction operators takeoff and landing distances by 12%. New aircraft gave conjugate wingtips , which reduce the load on the wing , but it also helps to improve the VPH . And cruising speed became higher due to lower resistance.

In the cockpit avionics suite with Garmin G5000 LCD screens replaced the old equipment Honeywell Primus 1000 , adding functionality and reducing aircraft weight by 90 kg. All this weight was removed mainly from the bow , so the alignment has shifted back , thereby reducing the balancing resistance , which also had a positive impact on efficiency at cruising . In conjunction with winglets it gives a gain of 4% range . At the same time , removing excess of 90 kg , the producers finally gave the operator the ability to find a satisfactory compromise between the fuel supply and the number of passengers.

Unlike the original model 45, Learjet 75 at the full range of standard equipment , including FMS functions WAAS, TCAS II, SVS and electronic cards. Standard left and APU Honeywell RE100, appeared on the 45XR. For ground operation it is almost vital as before starting the engine selected from the APU air powered Turbo-refrigerating unit ( TCA ) , heated seats and a conditioning or cabin. For this purpose, a ground power supply is not suitable.

The cabin has experienced a positive impact of a parallel program - the new Learjet 85, which now operates Bombardier. Offered only one configuration - double club . Each seat is equipped with a swivel mechanism , and extends into the passage , and the outer armrest removed if necessary . Located in the center of the salon four chairs are pushed back , too , creating more space for passengers , if the second half of the cabin is free.

Offered only one configuration - double club

Located in front of the kitchen interior unit is now much more storage space , which also organized more efficiently compared with the Learjet 45 . As an option, even offered a folding seat for the flight attendants next to the door .

Company Lufthansa Technik supplies for aircraft in-flight entertainment system , including an indication of aircraft position on the map. As an option, the player can buy Blu-Ray, satellite radio, video server , iPod- interface , optional 12-inch screens on the front and rear wall and individual 7 - inch monitors next to the seating area , as well as access to the Internet via Wi- Fi via satellite systems Aircell ATG and Inmarsat SwiftBroadband.

Learjet 75 has inherited all the best features of the Learjet 45 . Last was certified from zero in 1997 to the new standards FAR, Part 25 , Annex 77. This means that it is implemented with the permissible power structure damageability recognition engine failure within 2 to take into account when calculating takeoff performance , introduced a greater margin on flutter , there is protection against jamming of controls, there are separate , redundant control channels , passenger seats overload 16g, improved protection against ice and fire protection cabin. The only thing that got him from his predecessors - this design nose gear .

The glider is made of aluminum alloys , composites are used in the production of secondary structures. The outer layer of glass cockpit - glass. Trehlonzheronnoe with supercritical wing profile Bombardier developed using modern computer tools . The leading edge of the wing is equipped with various devices boundary layer control to improve handling at low speeds. Difficult to find a business jet with the same unit, more obedient to okolosryvnyh modes.

Aircraft systems are simple, with a high level of redundancy . The main controls are manual drive , hydraulic spoilers strengthen management on a roll . Rudder actuator , reducing pedal force , operates at speeds below 180 knots .

Refilling is carried out in a tank in the rear part of the fuselage, where a gravity fuel flows into the wing tanks . This design is typical for all Learjet.

In flight

The cockpit Learjet 75 well organized in terms of ergonomics . Frontal and lateral glazing review zakabinnogo opens space for 220 °. Besides, it 's pretty quiet .

The main improvement over the previous model is the new dashboard Bombardier Vision

Major improvement compared to the previous model , as mentioned above, is the new dashboard Bombardier Vision, which is based Garmin G5000 avionics suite with three vertically mounted 14 - inch monitors . The system is very informative , especially when compared with the previous Primus 1000 . Traditional blocks display FMS, radio panel settings and some other elements are replaced with two touch screens . Therefore, the programming of the flight plan is more like using an iPhone or iPad: all more or less intuitive. Like all navigation systems Garmin, radio frequency entered into the database . Generally, the system is designed so that pilots hardly ever have a question about what she is doing now . After commissioning in 2014, the manufacturer promises to add functionality , including all calculations for takeoff and landing , as well as opportunities FANS-1/FANS-A. In addition to automated and manual functions remained . For example, the fuel pump operates automatically and sealing system requires manually enter aerodrome .

During taxiing note that the brakes work smoothly and efficiently . In contrast to the nose wheel steering . Have to be trained to clearly fit into corners at low speed , because the pedals do not give any feedback on the neutral gear.

We take off from the airport Wichita , take-off weight 8165 kg, aerodrome - 400 m above sea level , the temperature of +31 ° C. In the right seat pilot Greg Bombardier Eastburn , he calculates the speed for take-off : separation speed 113 knots , 123 node in case of failure of one engine . Takeoff distance was 1300 meters I must say that both the speed and length of the runway taken from the reserve. Certification will reduce the rate of 2-4 knots.

Having received permission to take off from runway 19R, I deduce the throttle on takeoff and immediately realize that this aircraft although superficially similar to the Learjet 45, but the similarity ends . At least , it accelerates much livelier . Stabilizing at a speed of 250 knots , vertical speed 6-7 thousand feet per minute. We go on the train FL350 in 14 minutes .

At FL FL430 go to horizontal flight overboard -4 ° C , a cruising speed of 0.78 M (444 node true airspeed ) , fuel consumption 470 kg / h Gaining traction , exit at maximum speed 0.81 M (460 knots) , fuel consumption increased to 562 kg / h Definitely fuel efficiency - one of the biggest arguments in favor of Learjet 75 .

During reduction triggered system TCAS. Unlike some other systems, Garmin, G5000 Avionics in the Learjet 75 has no function of three-dimensional graphic display on the primary flight display (PFD). Instead pops up a small window with a two-dimensional image of the oncoming aircraft " bird's-eye " , the difference in height is displayed next in numerical form .

Test work on autopilot during approach RNAV. The system works precisely and smoothly . Execute a missed approach - in manual mode. Finally perform a soft landing , the brakes are working flawlessly.

Pays for what?

Catalog value Learjet 75 - almost $ 14 million , so that in the lightweight class to put it mildly , not the most affordable option . It is 4.5 million more than the Embraer Phenom 300 standard or Cessna Citation CJ4. Moreover, it is 700 thousand dollars more than the Cessna Citation XLS +, a complete class representative midsize. However, Bombardier says that buyers will appreciate the right plane , occupies an intermediate position between the sun light and the middle class , with a range of over 2,000 nautical miles , a cruising speed of 0.8 M and the APU as standard equipment .

Note . To make some of the strengths and weaknesses of a particular type , we compare its performance with the same cumulative averages aircraft of the same class . We calculate the average value of those characteristics which , in our opinion , determines the competitiveness of business jet . Then we calculate the percentage difference between the average value and the characteristics of the type described . For scheduling on Learjet 75 , we compared it with a group of aircraft, including but himself Cessna Citation CJ4 and XLS +, Embraer Phenom 300 , Gulfstream G150 and Learjet 60XR. The resulting graph is not a tool of direct comparison of one type to another , it just illustrates the relative strengths and weaknesses of the aircraft.

Payload with full fuel tanks Learjet 75 to 57 % higher than the nearest competitor, the Phenom 300 and 68% - the cumulative average in its class. Another competitive advantage is LTH : under standard conditions required for takeoff 1,350 meters , but if the length of the flight for more than 600 nautical miles, more. In the high altitude and hot climate Learjet 75 is a lot better than its predecessor , but still inferior to most competitors because of the high specific load on the wing . On the other hand , it is known , provides a comfortable stable flying in turbulence . Speed ​​and fuel efficiency - at altitude. Salon almost a meter longer than the competition in the lightweight class , is the only representative of the class , offering eight seats in two club sections and a flat floor . He even 40 cm longer than the Citation XLS +.

Although this arrangement is standard if all the seats are occupied , legs gets pretty crowded. Therefore, if you intend to mainly carry no more than four passengers , agree on the option of mobile access mechanisms that allow them more spacious and comfortable existence on board. Speaking of comfort : skirting along the wall is higher than the arms . Therefore, the left and right forearm (and, correspondingly , the shoulder ) carriers positioned at different heights.

As for the pilots , they will no doubt find something new equipment cabin Bombardier Vision, the basis of which the complex Garmin G5000 - a huge step towards them compared to the Honeywell Primus 1000 cabin Learjet 45XR.

And yet there is a few pebbles for this garden. Although Garmin develops autothrottles compatible with complex G5000, and delivers them to the Citation Sovereign and a new Citation X, but Learjet 75 this system is not, and she did not and would have prevented the aircraft at this price could go in standard equipment or even be offered as an option.

Not the easiest task is to steer, because the pedals do not give any feedback that informs the central position nose landing gear . And I must say that the efforts to control the roll and pitch , not changed since the Learjet 45, monstrous , even by the standards of other Learjet.

In general, Learjet 75, certainly much stronger competitor medium and light class than 45 and 45XR. Is he worth the money? Bombardier did not disclose details of the portfolio of orders . Aircraft Learjet family have always been appreciated for its versatility . Add to this improved VPH , new avionics and interior, and can say with certainty that their clientele will certainly find this plane .

Designers are doing their best to provide superior performance on all parameters , including the price . However, the laws of physics , thermodynamics, aerodynamics and fail to achieve the same efficiency in all within the same type. Compromises - reality aircraft design . For example , Learjet 75 - the only aircraft in its class, which has a flat interior floor that many operators appreciate . At the same time, the absence of recessed passage means that the height of the central axis of the cabin 5-10 cm less than that of her classmates.


Fred George