Reverser types are: Target type - The clam shells block the path of the exhaust and deflect it slightly forwards. Cascade type: - A clamshell in side the exhast "plugs" the tail pipe and the exhaust is forced out of cascade vanes in front of the "plug" or as the aft fan cowl moves aft (most common) ...Jump to post
The CFM-56B and C series engines on the -300 and -400 737 had no published (and therefore very unpredictable) acceleration times from Idle to 40% N1 (fan speed). So, the SOP is to get both engines to 40% N1 and then accelerate them together to T/O RPM. Any pause was the choice of the driver. B and C...Jump to post
The constant radius leading edges made their appearance on LearJets and were very effective and efficient. I'm supprised more aircraft aren't sporting them. The secret of lift on the BAe-146 is the aft translation of the flaps prior to lowering. Large wing area increase. Its part of that race car so...Jump to post
The 727 was designed without an APU. (Initially it was design with only two engines. This is why the APU is in the <acronym title="Meridiana Air (Spain) and Régionnair (Canada)">RH</acronym> wheel well. No CG margin left for a tail installation after the third engine #2 was installed.) USAir (now US...Jump to post
Straight 8s are "low" bypass engines. -200s are "medium" bypass engines. JT9s are "high" bypass. A J-75 turbojet is a no bypass.
Otherwise referred to as LRT = Little Round Things and BRT = Big Round Things.
Flameout vs Compressor flow reversal. If the engine is mismanaged (older types) you can cause it to lean the mixture out and have more air than fuel and litterally cause combustion to cease. This is the reason why ignition is turned on before landing as the throttles are constantly adjusted during l...Jump to post
I moved from Iowa last year. I probably saw your presentation.
Iowa has a lot of one man shops and small FBOs. From my own experience, I am interested in dealings with the FAA as they relate to violations as a shop owner.
I won't be there in 08 but say Hey, to Phil for me.
I was pushed back from the gate in a BAe-146 and had the opportunity to experience the ease in which hydraulics can be left "off". Dropped the tow bar and released the brakes to find the nose wheel steering inoperative. Logic prevented me from letting my feet off the brakes the second time. We sat t...Jump to post
Checkout the website for the ATF-3 engine for a look at an engine designed as close to the "ideal" engine as you can get. <a href="http://www.pocketprotectors.com/atf3/Engine.htm" target=_blank>http://www.pocketprotectors.com/atf3/Engine.htm</a> Cooling in the right places improves mass flow. Heatin...Jump to post
ACU = Compressor Bleed Control for JT8s. The range of JT8s makes any general statement impossible. Straight 8s (1-17R) and the -200 series. The -17s bore almost no resemblance to the very popular early -7s. -200s came with a real fan and very advanced compressor control. Acceleration times are very ...Jump to post
The sound is the exciters charging repeatedly as they fire the igniters. The exciters work much like a flash unit for a camera except the firing is determined by the gap in the outbound igniter connection. When the voltage in the capacitor gets high enough to jump the gap, the igniter provides the p...Jump to post
This is an excellent demostration of the "Coffin Corner" where the Mach limit and the stall speed meet. For subsonic aircraft like the U-2, the place is where you are a few knots from going supersonic or falling out of the sky in a stall.
Years of maintenance control experience alerts me that this is a procedural problem. The outter Anti-ice pane is very thin and is usually very hot. It is something that is very time restricted for ground operations. The inner (thick) panes are heated for defog and can be operated continuously. I hav...Jump to post
I design and implement databases to perform Maintenance Control functions at an airline. It is mostly getting the will of management in line to implement these new paperless systems. The computer systems now in place do a fine job of tracking and securing data. The problem is the older people in man...Jump to post
Removal of any installed antennas is a quick and easy job. Replaced the doubler with a solid doulber and put a flush patch in the skin hole. Use too much <acronym title="Prescott - Ernest A. Love Field (PRC / KPRC), USA - Arizona">PRC</acronym>-1422 for a real seal and have a happy. Look at installa...Jump to post
Anyone that yearns for the "Good Old Days" doesn't own a tool box. I've maintained working aircraft radials and they will suck up your time and blood quick engough for you to miss the sound of a satifying thump of a turbine enigne starting up. Change plugs every 25 hours? Change 25 gallons of oil ev...Jump to post
The problem may be more than just wires. The cabin systems, as previously mentioned, have computer networks to run the InFlight Entertainment. The small problems with wiring multiply when several systems or compoinents are using the same piece of clad steel to communicate. ARINC buses are a way of r...Jump to post
You can hear this sound replicated in any old style camera flash unit. The recharge ciruit charging up the capacitors. The ignitor units operate in the exact fashion as the flash units. A step up circuit increases the voltage to charge the capacitors through a pulse excitation (DC lacks the pulse of...Jump to post
BAe-146 was the four engine short range market champ. Became the Avro <acronym title="Royal Jordanian">RJ</acronym>-85/100. It NEVER got stuck out on some remote place. Four with one bad gets you three that will bring you home. In the bad days PSA changed every engine every 30 days. It still made sc...Jump to post
The gate race. Get those tires changed. The C-5 can jack it own gear. Onboard compressor for inflation and axel mounted valves for deflation. The mantra of tire change is: Worn to the cord, low on pressure, no pressure, blown, other tire on same axel low/blown, excessive heat from brake that causes ...Jump to post
Those three little lights? Those innocuous little handles? When they illuminate and the warning sounds - they are the biggest objects in the cockpit. Time slows down, your palms sweat and you get the feeling (instantly) that you want to be SOMEWHERE ELSE! Try standing in the wheel well when the APU ...Jump to post
Tail draggers are from the era of grass runways. The high traction afforded by touching down on pavement makes even the slightest mistake get magnified. I always recommended my tail dragger customers to maintain the highest recommended tire pressure when landing on pavement because it keeps the cont...Jump to post
The <acronym title="Air Madagascar">MD</acronym>-80 grew from the DC-9 in several ways. It got longer, so they put a longer landing gear on the <acronym title="Air Madagascar">MD</acronym>-80 to keep the tail from dragging on takeoff (kept the same nose gear). The wing is bigger so, they added a Zer...Jump to post
The CFM-56 on the 737-300 and -400 has a flat bottomed cowl. I heard a mechanic deadpan an explanation to a ramper that the fan blades were on a cam so they could "pull up" and get by the "flat spot". We had a great time confirming that story! Yep, that is the way it is! They eventually figure it out.Jump to post
Aircraft are certified with stopping distance by brakes alone. Thrust reversers are "auxilary deceleration devices". I have witness a DC-9 stop in less than 2k feet only reversers on an iced runway. FOD is the reason that most aircraft cancel T/R at around 60-80kts and brake from there. Brake and ti...Jump to post
I once had a senior mechanic ask me to look up the timing procedure for a jet engine, about a second later I realized I was being had. Doesn't help when you've spent a lot of time timing magnetos. I liked the military flight line. No shortage of "new" mechanics. There was a block in the forms titled...Jump to post
Those weights seem to be part of the rotor pitch change mechanism. Loss of a connection could be catastrophic but a flyweight could provide a very good safety by commanding the blade to a safe pitch. (Dassault Falcons have springs that neutralize control surfaces if they get disconnected from the co...Jump to post
The camera issue has been bouncing around the FAA and they are well on their way to putting video in the cockpit with the voice recorder (the Egypt Air crash left too many questions). They also want a cabin camera to view the cockpit door area and external cameras to monitor aircraft configuration. ...Jump to post
Wing mate and demate are a maintenance procedures that few mechanics in the airlines ever see. Quite common in business aviation. They put it together, it comes apart. USAir had a 737-300 wing replaced back in the late 80s. Got hit by a Cessna 310. Boeing did the work. As maintainers it is a good id...Jump to post
NOW THAT was a great idea. Self loading cargo. I suppose we've all experienced the remote gate transport that carries the plane load of people from the terminal to a "remote" gate. Now just stretch a little further to a 747 with a full width loading system where the passengers are preloaded into a "...Jump to post
Powerbacks were first approved at Atlanta for eastern airlines. It is an airport thing. Tail mounted engines work best. <acronym title="Air Madagascar">MD</acronym>-80, DC-9, RJs, etc. Cautions are exhaust ingestion and compressor stagnation due to elevated temps. The Feds view it there must be room...Jump to post
I must have missed something in the past few years away from the airlines. Last I knew, <acronym title="Trans Asia Airways (Taiwan)">GE</acronym> did a mod that eliminated (or reduced) mid-span shroud contact (clacking) because of wear to the hard coat where they meet. Something like some rubber blo...Jump to post
The igniters firing. Worked <acronym title="Air Madagascar">MD</acronym>-80s for years. The flash units on cameras work just the same and as you listen closely they will produce an very good imitation of an exciter box charging. Unlike the camera flash, the exciter box has an air gap trigger. When t...Jump to post
"Passengers reported seeing flames from the engine exhaust when moving away from the gate." I told them to have the people up front turn around and see the flames coming out of the inlet. When the EPA mandated reduction of "smoke" from aircraft exhaust the Pratts got an instant reputation for belchi...Jump to post
Sports fans! The JT8d would make a wonderful supersonic engine after the afore mentioned mods about inlet temperatures. The venerable J-75 (same engine family) is still driving supersonic and subsonic aircraft around the skies. The J-75 (15.5K/lbs no burner) could get to 1.1 before the compressor st...Jump to post
And here I though that semi-dried red hydraulic fluid was the best. Off in search of "Stick It". The question is: will it hold against rotation as well as duct taping the nut to your finger? I'll look for it but a tip from a guy with BIG fingers, I use all manner of short, long, and curved hemostats...Jump to post
I carried an electricians line belt and pouch with dykes, duck bills, safety wire pliers, safety wire, 1/4 ratchet, set of small snap on 1/4 drives on a rail, Apex driver with a film can of tips, some open/box end wrenches 3/8 to 9/16, a 6in cresent wrench, 3 cell mag light with halogen bulb (very s...Jump to post
The BAe-146 (RJ-85, etc...) has soft start to prevent the starter from breaking the starter pad off the gearbox (which they did). When I first worked on them, starting an engine sounded like a car crash immediately followed by a very fast crank up. Soft start saved the engines and the starters. The ...Jump to post
Gentlemen, Go back, way back to pistons. Aircraft were pressurized with very efficient compressors driven by shaft power of several varieties. Big advantage is they could be disengaged for operation when engine power was needed elsewhere. A combination of ram air and compressor would do nicely. Leak...Jump to post
There is a factor to consider in "weaker bolts". They lack the strength to hold their form under stress above their rating, but they will first, deform under overload rather than fracture and fail. The <acronym title="Carpatian Air Transport (Hungary)">KC</acronym>-135 had cracking problems with it ...Jump to post
There are no good answers and it is an ever changing environment. In the beginning, mechanics built and flew airplanes (Orville, Wilbur, and Glenn). Pilots that didn't wrench came into the system slowly. It was painfully apparant to crews how much work it was to maintain piston aircraft by the const...Jump to post