page 45 - American Bonanza Society

More documents

Recommendations

Info

Tech Tips Tech Tips are answers to questions about a specific airplane, system or operation presented by an ABS member, and are the opinion of the Technical Advisor. Answers are the best information available based on indications presented by the ABS member asking the question. Actual inspection of the aircraft or system in question may change an initial Tech Tips opinion. Aircraft owners, pilots and readers are advised to physically present airplanes and indications to a qualified mechanic before choosing a course of action. Bob Ripley retired from Delta Airlines as a manager of line mainte nance (Atlanta) and has run an FBO focusing on Beech maintenance for 20+ years. Curtis Boulware has managed a Bonanza, Baron, and T-34 Mentor-specific shop for 13 years, winning numerous national awards for T-34 restorations. He earned his Private in a T-34 and enjoys flying all models of the Beech piston family. John Collins has previously owned an FBO and avionics shops, and for several years has been ABS’s Avionics columnist. He owns a Bonanza and is a CFI/CFII. Dan Honeycutt is an A&P/IA with over 20 years experience. He owns a California-based FBO specializing in Bonanzas and Barons. Arthur Miller has won numerous FAA awards as a mechanic, and runs a Beech specialty shop in central Florida. Tom Turner, ABS-ASF Executive Director, holds a Master’s degree in Aviation Safety. He has specialized in Beech pilot instruction for over 20 years. Q: Prop vibration in cruise Skip Bakos, Crown Point, Indiana I own a 1998 B36TC with the Tornado Alley turbonormalized conversion. The plane sat idle for a little more than two years due to some “life issues.” During that time, there was a humidity problem in my hangar that caused considerable rust damage on the cam, lifters and other rotables. These problems were repaired by two very well known and trusted Bonanza airframe and engine shops. We’ve been flying the aircraft often now for the last four months, having logged some 35 or 40 hours during this time. During start-up, run-up, taxi, and take-off the plane is amazing. It performs as expected and provides all of the required power to climb away safely. During the climb, the plane is smooth as can be and all engine gauges are within their desired ranges. The major problem we had before the required engine maintenance was that TIT would exceed the maximum 899 degrees Celsius on the takeoff roll and would not be achieving the appropriate power. During the climb-out we are at full power, full prop, mixture set to 35 gph, cowl flaps open, gear up, and climbing at about 120 knots with the remaining engine gauges all in the green (normal) operating range. The issue we are having is when we climb to the desired altitude (doesn’t matter if it’s 4000 feet or 10,000 feet) and start to level off and accelerate towards our desired 160-ish knots indicated. Following the checklist step by step, we close the cowl flaps (while maintaining close eye on CHT not to exceed 380°F), maintain full throttle (which is about 30.1" MP), smoothly bring the prop back to the desired 2500 rpm, and then in the 3-5 seconds (as the checklist states) lean the mixture to between 16.0-17.5 gph while maintaining a close eye on the TIT peak and also CHT. Leaning the mixture to LOP and about 17.5 gph gives us about 1540°F TIT based on the JPI and all CHT below the specified 380°F. Once we are fully configured for cruise, we begin to feel a vibration in the seats, floor, and rudder pedals. In my opinion it feels like the prop is not in sync with the engine. This feeling does not happen every time, and when it does it only lasts for a couple of minutes at the most. During the vibration, all of the engine gauges remain right where we put them. We have made sure that the cowl flaps were fully closed (in case it was vibration from them) and even opened them a little in case they were hitting the cowling, but didn’t change the feeling at all. The one thing that has made the vibration go away (based on a recommendation) was to change the pitch of the prop by any amount. We have reduced it to 2490 rpm and the sensation went away. We would then bring it back to the specified 2500 rpm and the vibration sometimes happens again. We have been asked multiple times about making sure we aren’t flying between 2350-2450 rpm at or above 24" MP and we definitely are not! We also have felt the vibration when we start our descent without changing any power settings yet. When we receive a lower altitude we first get the plane pitching over at least 100-200 fpm and with the desired altitude armed before decreasing to the 23-25" MP, 2300 rpm, and while maintaining the cruise mixture setting. While maintaining these specified settings throughout the 58 AMERICAN BONANZA SOCIETY MAY 2013
www.bonanza.org entire descent we start the level off procedure. Depending on how far from the airport we are sometimes we maintain the 23-25" and 2300 rpm. However, if we still have some distance to go we will bring the throttle back to full WOT and leave the prop spinning at 2300 rpm. We have never felt this vibration with the prop set to 2300 rpm. To sum it all up, the vibration we are feeling has happened at all altitudes and with full throttle and propeller set to 2500 rpm. Changing the prop has been the only thing that has made it go away instantaneously. Any ideas or suggestions? Everyone I’ve talked to is stumped. A: It sounds like you have developed a harmonic issue with the propeller and fuel flow settings. I have seen this problem happen on some engines when operating LOP. Next time it happens try to richen mixture slightly and see if that helps. If not, you may want to have the propeller dynamic balanced. Please advise us on what you find, it may help another member in the future. —BR Q: Repairing rheostats Keith LeMahieu, Frankfort, Illinois The panel and overhead flood rheostats are almost gone on my S35. Only the highest setting is operative. What are my options to repair? Are there any new STC’d products? Where is the best place to locate replacement parts? What will the cost be? What advice do you have? The part number for the rheostats has changed A1: from the original and they are now both the same part number, which is H10-F2-351. The cost is $411.84 from Beechcraft. The reason the rheostats are costly is because the post lights draw a large amount of amperage due to the quantity of lights. There are no approved STC replacements available. You can convert all of the instruments to the Nulite, which can be purchased at Aircraft Spruce: www.aircraftspruce. com/catalog/elpages/nulite3.php?clickkey=9386. These lights draw extremely little amperage and provide much better illumination for the instruments. You can then install a smaller rheostat which based on the amperage draw for all of the lights it supplies. —BR You also have the option to install the transistorized A2: dimmers from MaxDim. They are STC’d for the Bonanza, cheaper, and can handle more current. See www. aircraftspruce.com/search/search.php?s=MAX+DIM&x=- 572&y= -180 . There are several types of connections offered, so make sure it matches your rheostat. —JC We share your love for Beechcraft, which is why we own one too! Marisa (Reese) Leach A&P/IA Mechanic Professional Engineer Commercial Pilot 30+ Year Aircraft Owner Jim Leach A&P Mechanic Professional Engineer Commercial Pilot & CFII US Naval Aviator 40+ Year Aircraft Owner We work on a lot of aircraft, but Beechcraft is our favorite brand. That’s why we own one, “G-Whiz”, a 1956 G35 Bonanza. Beechcraft are built to last - with the right maintenance plan. Next time your Beechcraft needs service, please give us a call at Windward Aviation. We will treat your Beechcraft as if it were our own. Maintenance • Upgrades • Repair & Restoration Avionics • Propeller • Flight Test & Delivery Paint & Interior • Detailing • Hangar Space 1-800-546-8668 Palm Beach County Airport (KLNA) Professionals Serving General Aviation www.windwardaviation.net Volume 13 • Number 5 AMERICAN BONANZA SOCIETY 59
Page 1 and 2:
May 2013 VOLUME 13 • NUMBER 5 BPP
Page 3 and 4:
May 2013 VOLUME 13 • NUMBER 5 The
Page 5 and 6:
President’s Comments It’s A Sma
Page 7 and 8:
REPORT Volume 13 • Number 5 AMERI
Page 9 and 10: www.bonanza.org and introduce them
Page 13 and 14: ABS Air Safety Foundation By Thomas
Page 15 and 16: www.bonanza.org Instructor list on
Page 17 and 18: www.bonanza.org h. The flight shoul
Page 19 and 20: …so don’t be surprised if you s
Page 21 and 22: www.bonanza.org I fly my Bonanza ap
Page 24 and 25: Currents By Lew Gage LOP with an E2
Page 26 and 27: www.bonanza.org This spark plug rea
Page 28: The Best Planes at the Best Prices
Page 31 and 32: Figure 5 It produces an orbital rot
Page 33 and 34: Upcoming Fall Flight Clinics: • T
Page 35 and 36: www.bonanza.org Fire, windstorm, va
Page 38 and 39: www.bonanza.org Turbos and Low Alti
Page 40 and 41: Your Northeast Beechcraft Experts I
Page 44 and 45: Safety Pilot By Thomas P. Turner Th
Page 46 and 47: www.bonanza.org Every one of the hi
Page 48 and 49: Testimonials “ I appreciate very
Page 50 and 51: BPPP By Mike Friel Obstacle Avoidan
Page 52 and 53: www.bonanza.org OVER 1,000 SETS SOL
Page 54 and 55: www.bonanza.org Mexico, Close and E
Page 56 and 57: www.bonanza.org There is so much mo
Page 58 and 59: www.bonanza.org fiestas, and grassh
Page 62 and 63: Major Sheet Metal Repairs, Flight C
Page 64 and 65: Q: E-185 with a Hartzell propeller
Page 66 and 67: Family Owned and Operated Since 197
Page 68 and 69: ABS at Sun ’n Fun ABS greeted ove
Page 70 and 71: CUSTOM ENGINE OVERHAULS NEAR CHICAG
Page 72 and 73: We Need Your Photos! Attention ABS
Page 75 and 76: www.bonanza.org Classified Advertis
Page 77 and 78: www.bonanza.org Beechcraft Instruct
Page 79 and 80: Flight Controls Re-Skinned. We resk
Page 81 and 82: w Additional details are available
show all

page 45 - American Bonanza Society

Create successful ePaper yourself

Delete template?

Save as template?