Learjet Winter 2004

• ELT Situation Supports Solid RVSM Date
• Learjet Cockpit Blower Receives FAA/PMA Approval
• 31A RVSM
• Horizontal Stab Actuator

ELT Situation Supports Solid RVSM Date

— Dave Schiver

Just as the 01/01/2004 ELT mandate stood firm, we believe the FAA will not budge on the 01/20/2005 RVSM and 05/29/2005 TAWS mandates. Equipment shortages and mods shop schedules left many last minute ELT shoppers unprepared for the mandate, but many of them kept flying by installing a 121.5 MHz ELT until a 406 MHz installation date and equipment is available. We believe RVSM and TAWS will make the ELT crunch look like small potatoes and there will be no short-term fixes. While many pilots assume they will simply "file for FL270 if the date sticks," there will be great demand for the highest non-RVSM altitudes from noncompliant jets and high-flying turboprops. This will result in even lower available altitudes which translate into more fuel consumption and refueling stops for passengers used to nonstop flights. Now is the time to gather the facts and take action toward meeting these mandates. If you have TAWS or RVSM questions, call us for a free copy of Straight Talk about TAWS or our recently released Straight Talk about RVSM: 2nd Edition or visit DRVSM.com.

Learjet Cockpit Blower Receives FAA/PMA Approval

— Chris Gress

The EM608-1 (alt# 6608267-2 & 2619387-2 & -3) replacement "Brushless PMA Cockpit Blower" has received FAA/PMA approval. Units are immediately available as "exchange units" for an introductory price & period of time. This is not an STC, 337 paperwork is not required to install this unit.

This Electromech Technologies blower is applicable to Lear 24, 25, 31, 35 & 36 models. The warranty period of this blower is three years. This results in a longer cockpit blower life, representing substantial savings. For immediate availability, contact Chris Gress at 800.228.4277 ext. 1664.

31A RVSM

— Dave Schiver

Duncan Aviation recently discovered an error in the Learjet Maintenance Manual regarding the Air Data System Functional Check. In Chapter 34-16-00, Page 203, Step (k), the text states "When aircraft's displayed altitude has reached the selected altitude of 28,000 feet, verify a 3 second pause, after which the aircraft altitude shall ramp down to 27,000 feet at a 6000 feet per minute rate of descent with an altitude alert tone at 27,800 feet (27,700 feet optional)". This is a true statement for the pilot's side. At Step (m), it asks you repeat the section for the co-pilot's side. At this point, the altitude alerter tone is not functional per 34-16-00. 1.B (1) (g), it states "Signals for altitude alert aural and visual warning on pilot's side and visual warning only on co-pilot's side." Now in the Service Bulletin for RVSM (31-34-11), it does the same F/T but there is no note that the aural warning will not function on the co-pilot's side. This is because the wire is not installed from pin "M" on the co-pilot's Altimeter/ VSI (KAV 485) to the auto-pilot electric box (AP232 pin "3"). Learjet is aware of this issue.

Horizontal Stab Actuator

— Chris Gress

The Learjet Horizontal Stabilizer Actuator utilizes two motors, an emergency motor and a primary. These, along with the stab actuator are inspected every 600 hours. These motors are a brush and armature design, so the brushes are a determining factor whether to replace the motor or not at the 600 hour inspection.

Another common problem areas on these motors is the clutch and brake. Duncan Aviation technicians are trained by the manufacturer to repair these motors, including clutch and brake shimming. Sometimes a slight shimming adjustment can be performed to compensate the friction material with wear, saving operators several hundred dollars over replacing the motor.

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