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iChris

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About iChris

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  1. You don’t need to rebuild the R22/R44 helicopter or overhaul its engine. However, regardless of the certificate, the aircraft has to be airworthy. It is well-established that an aircraft is deemed 'airworthy' only when it conforms to its type certificate (if and as that certificate has been modified by supplemental type certificates and by Airworthiness Directives), and is in condition for safe operation. Experimental won’t get you pass that. It's a documented practice in line with FAR 43.15c and Appendix D to Part 43. If the aircraft is not used for compensation or hire it could be operated part 91 under the annual inspection only requirements of 91.409a. In that case (with respect to the engine) there would be no required engine overhaul. You could continue on each year as long as the engine passes the annual inspection requirements in Appendix D to Part 43. That’s your on-condition operation. Also, as long as the owner complies with chapter 3 page 3.9 or page 3.10 in the R22 maintenance manual, the aircraft and engine can be maintained under FAR 91.409a, 43.15c, and Appendix D to Part 43 in an airworthy condition. To fully understand you may need to read the posts below and the supporting documentation. R22 Airworthiness past 2200hrs/12yrs R44 12-Year Inspection Required for Part 91? Legal Interpretation MacMillan Apr 22, 2011 FAA Order 8620.2B - Applicability and Enforcement of Manufacturer’s Data
  2. NTSB Updates on Kobe Bryant Accident A ground camera captured an image of the helicopter entering the clouds. Radar/ADS-B data indicate the aircraft was climbing southwesterly along a course aligned with Highway 101 just east of the Las Virgenes exit, between Las Virgenes and Lost Hills Road. The helicopter reached an altitude of 2,300 feet msl, approximately 1,500 feet above the highway, but below the surrounding terrain when it began a left turn. Eight seconds later, the aircraft began descending as the left turn continued. The descent rate increased to over 4,000 feet per minute while the ground speed reached 160 knots. The last ADS-B target was received at 1,200 feet msl approximately 400 feet southwest of the accident site. A still photo obtained from a security camera located in a road maintenance yard adjacent to Mureau Road and Highway 101 showed the helicopter proceeding westward along the highway and disappearing into the clouds. Mureau runs just to the north of Highway 101. The Board as yet does not know why the pilot entered the clouds. NWS photo looking east from a hill near the crash indicates the tops of the clouds near the site were about 2,400 msl. Full text: NTSB Updates on Kobe Bryant Accident By Rob Mark
  3. The quote was Aviation accidents.... Job-related mortality of wildlife workers in the United States, 1937-2000 “Abstract Wildlife biologists face a variety of job-related hazards that are unique to this profession, most of them involving the remote areas where work is performed and the unusual techniques used to study or manage wildlife. Information on biologists and others killed while conducting wildlife research or management was obtained from state and federal natural resources agencies, solicitations on wildlife-based internet discussion groups, and published obituaries. Ninety-one (91) job-related deaths were documented from 1937 to 2000. Aviation accidents, drowning, car and truck accidents, and murder were the most common causes of death. Thirty-nine (39) aviation accidents accounted for 66% of deaths, with aerodynamic stalls and power-line collisions being the most significant causes of accidents for which information was available. These safety threats should be taken into consideration during the design and planning of future research and management projects.” REF: https://www.jstor.org/stable/3784446?seq=1 Some communities have enacted zoning laws, building codes, fire regulations, etc. that can affect establishment of helicopter landings in residential neighborhoods. They’ve developed codes or ordinances regulating environmental issues such as noise and air pollution. A few localities have enacted specific rules governing the establishment of a heliport. Therefore, contact officials or agencies representing the local zoning board, the fire, police, or sheriff's department, City Council, and the Mayor’s office. Get with your neighbors, kill it at the local level, and the FAA will not approve it in opposition to local laws. Also: http://stophelipad.org/home.shtml
  4. That S-76B was operated single-pilot VFR, Part 135 charter, limit 9 PAX seats. That wasn’t an IFR operation. That’s also why neither Cockpit Voice Recorder (CVR) or Flight Data Recorder (FDR or Black Box) are required (135.151 or 135.152).
  5. The 90gal/hr is a bit high for single engine operation. However, that's in the range with both engines online, 0.5 - 0.6 (80 - 97 gal/hr ) in terms of efficiency, you're looking for < 0.7 SHP(takeoff) = 1100 (0.5 * SHP)/6.8 = 80gal/hr (0.6 * SHP)/6.8 = 97gal/hr
  6. There’s a typical 0.5 - 0.8 Ibs/hp/hr specific fuel consumption (SFC) index for modern turbine engines. Light helicopter turbines, 0.5 is a good average The Bell 429’s one engine inoperative (OEI) 30 minutes hp = 550 SHP. So your OEI would average around: 40gal/hr. @550 SHP (jetA est. 6.8lbs/gal)
  7. You take calculated risk every time you go and fly. It’s how you manage that risk, how you plan ahead for it, and deal with it that makes it dangerous or not dangerous. One thing is sure, dangerous or not, it’s unforgiving of poor decision-making
  8. Delorean’s post above gives an excellent description of the system. The system is fairly simple. You have a solid-state control unit mounted behind the left seat back. The controller senses engine RPM via tachometer points in the engine right magneto and provides a corrective signal to the governor assembly. The governor assembly gearmotor is attached to the collective stick assembly behind the left seat. When activated by the controller, the gearmotor make the required RPM adjustment by driving a clutch connected to the throttle. The following is a quote from the R22 maintenance manual: “The majority of governor problems are caused by the engine's right (helicopter left side) magneto tachometer contact assembly (points) being out of adjustment or faulty.” Garbage-in garbage-out, engine right magneto or wiring problems upstream of the controller can result in strange or intermittent issues. The controller may not be the problem. Check out the link below pages 8.34A RPM Governor System and 8.34C Governor Troubleshooting https://robinsonheli.com/wp-content/uploads/2018/11/r22_mm_8.pdf click photo to enlarge
  9. Cavitation can be recognized by sound. The pump will produce either a whining or a rattling sound. If you hear either, you'll need to determine the source. These sounds don’t guarantee a hydraulic system problem. Flow restrictions, buildup in the strainers, filters, or shutoff valves not fully opening are often causes of cavitation. High oil viscosity, oil that is too viscous and will not flow easily also causes problems. Oil viscosity must be appropriate for the climate and application. Correct any fluid leaks. Likely there's not much wrong, the R44 hydraulic system is fairly simple. Maybe just a loose fitting or replacement of the 10-micron filter. You’ll need more evidence of a problem, beyond what you’re hearing.
  10. The 250-C30 compressor bleed air system permits rapid engine response. The system consists of a bleed control valve located on the front face of the scroll and an inducer bleed manifold which encases the slotted compressor shroud housing. The inducer bleed system is composed of circumferential slots on the impeller inducer shroud, a circumferential collecting plenum, and a bleed port which is located clockwise from the top dead center. At low speed, the inducer bleed system bleeds air out, increasing air flow rate at the face of the impeller, which reduces inducer angle of attack and decreases the chance of inducer stall. This improves part speed stability, especially near 85 % N1, where the At high speed, the bleed system sucks in air from outside, which reduces inducer choking. On the standard operating line, bleed direction changes between 95% to 100% N1. The compressor receives air at the center of the impeller in an axial direction and accelerates the air outward by centrifugal reaction to its rotational speed. At the lower rotational speed some air bleeds off via the inducer bleed port. As rotational speed increases and the air continues its acceleration, the static pressure decreases according to Bernoulli’s Principle. This continuing reduction is static pressure at the impeller, versus outside ambient pressure, works to eventually choke off the inducer bleed air and allows air flow in through the bleed.
  11. We need to understand the system we’re dealing with. The pump doesn't pump pressure. The pump delivers a rate of flow and that rate of flow meets with and hopefully overcomes resistance in the system. What you’re reading on the gage is not the amount of pressure the pump is putting out. What you’re reading is the amount of resistance being overcome downstream of the gage. Contrary to your quote, 10 PSI represents low resistance and adequate flow rates. The difference between pressure and flow is often misunderstood. The CH47 aft transmission lubrication system, see photo below, is a parallel-series system where the pump is servicing multiple branches. The branch could have multiple series loads or additional parallel flow paths. These parallel and series combinations behave differently and have branch pressure that differs from the overall system pressure. The transmission pressure is taken downstream of the filter. The filter and transmission resistance to flow causes a pressure drop. The physics of this series branch states the sum of the pressure drop must equal the system pressure. Under normal operations, 6-10 PSI is needed to overcome filter resistance resulting in a 6-10 PSI drop across the filter. The remaining 14-10 PSI is dropped across the transmission. Problems with the system similar to filter blockage or blockage downstream of the filter will increase the pressure drop across the filter, and reduce flow into the transmission. The physics are satisfied by an increased pressure drop across the filter and decreased pressure drop across the transmission. The total of all pressure drops in the branch remains equal to system pressure. Without the transmission pressure information, we would never have known there was a problem, since the system pressure is still at 20 PSI, see photos below. click photo to enlarge [media]https://youtu.be/AyizWUpPt28[/media] '>https://youtu.be/AyizWUpPt28 '>https://youtu.be/F4VM_Xlp-SU
  12. There’s been much written on the canted tail on the H-60, as evidence in this post; however, you must analyze the tail section dynamics in its entirety (tail rotor, tail pylon, vertical stabilizer, horizontal stabilator, microprocessor controlled stabilator-incidence angle, etc.). Numerous technical papers and article from NASA and others, two listed below. “Some basics first: The canted tail rotor is tilted so that some of the rotor thrust is directed upward, which means it contributes to the total lift of the aircraft. The cant angle is 20 degrees, so the tail rotor thrust in the vertical axis is over 30% of its total thrust, while the horizontal axis retains about 94% of the total thrust, a small cost to pay for that lift. The two benefits for the H-60 and H-53E are that the lift from the tail rotor help the CG of the aircraft. The 53E third engine was added to the 53D and was placed aft of the transmission, so the tail rotor was used to retain aircraft balance. For the H-60, the aircraft was designed to fit inside a C-130, and so was made low and longer relative to its required payload and volume. The tail rotor helped the designers retain good longitudinal balance. For the other aircraft with canted tails, the S-92, the AW-139 and the Bell 525, the lift from the tail rotor helps payload. For the S-92, the canted tail rotor is worth between one and two extra passengers." ”Nick Lappos, Technical Fellow Emeritus You can also download Ray W. Prouty's article titled, Evolution of Sikorsky Tails, link below: Center of Gravity & Evolution of Sikorsky Tails
  13. The video below was made by one of the vendors that supplies those type of cables to Sporty’s and others. The issue you described is very similar to an issue related to cables with a given type of recessed receptacle, both airplane and helicopter. Some of these receptacle types make a very tight connection. They sometimes can be both hard to connect and disconnect. Moreover, if you didn’t hear a distinctive click, it wasn’t fully connected. When it’s fully connected, the click is very distinctive. The video is a consequence of the number of customer returns. Electrically the cables is sound; however, an appreciable amount of force is required to make a good connection. Alternative choice, link: GA Fixed Wing Aircraft to Helicopter Headset Cable Adapter '>https://youtu.be/Ugk63QJVj5E
  14. No direct experience with the modems you listed; however, I've used a similar model, the Pepwave MAX BR1 Router with WiFi 3G/4G/LTE Modem. Worked fine over large metropolitan areas were the cellular antenna was mounted to the bottom of the aircraft and most all flights were below 1.5 AGL. My experience mostly over Seattle, Portland, Sacramento, San Francisco & Bay Area, Los Angeles Area, San Diego, again flights below 1.5 AGL. Cross-country flights over sparsely populated areas, mountainous terrain were uninterrupted cellular communication is required, move on to satellite. It’s ironic that you brought up another form of that acronym, LTE, that’s also confusing and misunderstood. The International Telecommunication Union (ITU) was established to set standards and specifications for global telecommunications and communication technologies. That includes all cellular communication technologies. The 1G – 5G networks we hear about are the levels or generations of standards and technical specifications set by the ITU. When the ITU set the fourth generation of standards (4G) a decade ago, none of the cellular companies could meet the full implementation of those standards. The ITU sets goals in advance of the current technology and it was meant to be an evolutionary process for future goals in communication technologies. One of the many specifications at that time was a minimum and maximum bit rate. The minimum bit rate was 100Mbps download, maximum 1Gbps download and 500Mbps upload. Most didn’t meet the full implementation of the standard not even the minimum, but they were still calling it 4G. Consequently, the ITU got involved and they said okay, we’ll use the 4G designation even though you don’t meet the full implementation and we’ll refer to it as 4G Long Term Evolution (4G LTE). As companies came within reach of the full implementation of the 4G standard, they ran into a small problem, a marketing problem. We can’t drop the LTE from our designation, that would open up questions and maybe telling customers the real reason, we’re just now meeting the full implementation for 4G. We need to do it another way. Drop the LTE and call it 4G Advanced or 4G Plus. I don’t know if some of you recall when AT&T jumped out with their so-called 5G. They had to take a step back, now they refer to it as the 5G Evolution. The 5G at last quote, ups the ante, 1Gbps upload minimum and 20Gbps upload maximum.
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