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djpacro

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  1. Me too, I left after Andrew’s display in the Extra - the heat affected his performance too. Even then it took ages to get out of the car park. Quite a few people there, especially with that weather, so they would’ve been happy with their publicity. I would’ve flown in if the weather was better and I’d have offered red750 a seat.
  2. I heard a rumour that Rich Stowell is visiting Australia soon for some seminars and flight training.
  3. Someone happened to catch it on video.
  4. Try this Collision with terrain involving DHC-1, 'Chipmunk' VH-UPD near Coffs Harbour, NSW on 29 June 2014 | ATSB
  5. I don't see any of that in the report? Nowhere do I see a mod to the stick grip however there is mention that harness may restrain positioning of the stick.
  6. Not altogether, there's a wealth of information from NASA's GA spin research around the '70s which contributed significantly. I don't know what you mean about eroding "the original certification requirement"? I see some significant differences between CAR3 and FAR23 (the versions that applied to many aircraft around today). The latest FAR 23 is different again. I'll have a look for that older spin material, thanks.
  7. A recent USA AOPA article is relevant: https://aopa.org/training-and-safety/air-safety-institute/accident-analysis/flight-training-accident-report CASA issued AC61-16, Spin avoidance and stall recovery training , about 4 years ago which is consistent with Figure 5-10 of the Airplane Flying Handbook. However, the CASA Flight Instructor Manual has not been revised per ATSB Investigation AO-2017-096 of 22/5/2019. In the USA: Not so per the Australian Transport Safety Bureau AR-2020-047 Aviation Occurrence Statistics (rates update) 2010 to 2019 (the latest data): To repeat: in the USA flight instruction safety has improved whereas in Australia it has worsened. From Issue 107 of SportPilot Magazine we have this: Fine as far as it goes however, I didn't see any guidance on the use of rudder. It states to "level the wings" without explaining the technique. Better to stick with the FAA's Figure 5-10 and associated text of the Airplane Flying Handbook.
  8. If one believes CASA's Flight Instructor Manual one would believe that the recovery method from an incipient spin is different from a fully developed spin. Identify when one is no longer in an incipient spin and suddenly the recovery action is different. See my extract from Cessna's Spin Booklet above, repeated here: "During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflections. However, positive spin recovery control inputs should be used regardless of the phase of the spin during which recovery is initiated." The test pilots and engineers who write the bits ablout spinning in flight manuals follow FAA AC 23-8C FLIGHT TEST GUIDE FOR CERTIFICATION OF PART 23 AIRPLANES which defines the spin: No mention of the word "incipient" at all in that document. When the word "spin" or "spinning" is used in the AFM or POH then it simply means "a sustained autorotation" and use the method in that AFM/POH for spin recovery. That is especially important for types not approved for intentional spinning as they have only been tested for recoveries from a spin of up to one turn. Picking up that Cessna statement again: "During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflections." "may occur" ... well, of course, the spin behaviour is changing all throughout the incipient spin phase so don't expect that to work at the instant just prior to the established fully developed spin. However, it is a good technique for aerobatic pilots, in a type approved for intentional spins, at the onset of autorotation to centralise the controls and close the throttle.
  9. I noticed this site promoting CASA's Flight Instructor Manual. One would expect CASA’s Flight Instructor Manual to be a reputable source of correct information on spinning however ATSB Investigation AO-2017-096 of 22/5/2019 found otherwise. When that ATSB report was issued “CASA has advised the ATSB that they have taken the following safety action …..” i.e. they reviewed the above text in the Flight Instructor Manual but took no action so they must believe it to be correct.
  10. One of the gems is Cessna's booklet which was published back in the '70s to counter misinformation about spinning. About time that it was promoted again. https://mikeklochcfi.files.wordpress.com/2018/03/cessna-spin-manual.pdf It has much general information (obviously a lot of information speciific to the Cessna so be careful about generalising) too with information such as: "For the purpose of this discussion, we will divide the spin into three distinct phases. ..... Here, in the entry phase, recovery from or prevention of the spin is as simple as normal stall recovery since, in fact, at this point that's all we are really faced with. .... During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflec- tions. However, positive spin recovery control inputs should be used regardless of the phase of the spin during which recovery is initiated. .... Due to the attitude of the airplane in a spin the total motion is made up of roiling and usually pitching motions as well as the predominate yawing motions. Movement of the airplane flight controls affects the rate of motion about one of the axes. Because of the strong gyroscopic influences in the spin, improper aerodynamic control inputs can have an adverse affect on the spin motion. .... Some of the additional factors which have (or may have) an effect on spin behavior and spin recovery characteristics are aircraft loading (distribution, center of gravity and weight), altitude, power, and rigging. Distribution of the weight of the airplane can have a significant effect on spin behavior. The addition of weight at any distance from the center of gravity of the airplane will increase its moment of inertia about two axes. This increased inertia independent of the center of gravity location or weight will tend to promote a less steep spin attitude and more sluggish recoveries. Forward location of the c. g. will usually make it more diffi- cult to obtain a pure spin due to the reduced elevator effectiveness." I mentioned that effect of moment of inertia in another thread. Pilots get to determine weight and CG but, as Cessna stated above, the increased moment of inertia is independent of weight and CG. eg fuel in outboard wing tanks vs inboard wing tanks. However, we usually deal with small changes in weight and CG associated with a large change in moment of inertia. Pilots have been be caught out with small ballast weights added near the tail to adjust CG with no consideration given to the moment arm squared and the big increase in moment of inertia. What some pilots (or the accident investigators) have observed to be the result of a small CG change was actually caused by a change in moment of inertia. NB: the USA FAA supported this booklet with their bulletin to all flight instructors back then.
  11. This is obsolete. The new one has an additional chapter and lots of other changes.
  12. A spin resistance standard was added to the FAR 23 airworthiness design and testing requirements in 1991. The Columbia 300 was certified to this standard in 1998. It carries clear warnings in the POH "Do not attempt to spin the airplane under any circumstances ..... During the flight test phase of the airplane's certification, spins were not performed. It is not known if the airplane will recover from a spin." The Cirrus was certified with an Equivalent Level of Safety by having the CAPS. Perhaps considered to have a spin resistant wing design as they followed some guidance from NASA with this. Anyway, the Cirrus spin certification and some spin testing done for EASA is a longer story for perhaps another day as it is slightly off topic.
  13. Spin resistant does not mean that it won't spin nor that, if it does, it will recover. A spin about 2 minutes into this video. Just because it recovered from this spin does not mean that it will recover from other spin modes. J
  14. "The way in which the mass of an airplane is distributed between the wing and fuselage is the most important single factor in spinning because it determines the way in which the airplane, while spinning, responds to control movements, especially to elevators and ailerons. An airplane rotating in a spin can be considered to be a large gyroscope. Since there are mass and angular rotation about all three axes, inertia moments are produced about all three axes." Fig 3 shows the balance of pitching moments in a spin which basically determines the angle of attack in the fully developed spin. The nose down aerodynamic moments vs the nose up moments from inertia. Worth repeating NASA's statement: "The way in which the mass of an airplane is distributed between the wing and fuselage is the most important single factor in spinning ..." NASA is not referring to CG there but to the moments of inertia. "In order for the airplane to recover from the spin, the equilibrium must be broken, and this is normally accomplished by changing the aerodynamic moment by moving a control or combination of controls that can cause the greatest antispin moment. ....... The loading of the airplane dictates the control movements required for recovery. ..... Deflection of the rudder to oppose the spinning rotation directly is always recommended, but in many cases, it is not adequate to provide recovery. For the wing-heavy loadings, down elevator is the primary recovery control." "Three factors are of almost overriding importance with regard to spin and recovery characteristics: (a) The relative distribution of the mass of the airplane between the wing and fuselage, which is commonly expressed in terms of the inertia yawing-moment parameter, a nondimensional factor relating the rolling and pitching moments of inertia (b) The tail configuration, which must provide damping for the spinning rotation and the rudder power for recovery and which is commonly evaluated in terms of an empirically determined tail-damping power factor (c) The density of the airplane relative to the density of the air, which is commonly expressed in terms of the relative-density factor" We don't need to concern ourselves with effects of air density so just moments of inertia and tail design. Some aircraft types have weak nose down pitching moments so the nose up inertia moments drive them towards a much higher angle of attack in the spin. NASA has shown this for the Grumman AA-1
  15. CASA's Part 61 MOS requires this as essential knowledge for all pilots: "Differentiate between a spin and a spiral dive in a light aeroplane and describe the standard recovery technique for each manoeuvre." Yet I regularly encounter pilots and students who do not know the "standard" recovery technique for a spin. Worse, I regularly encounter flight instructors and trainee flight instructors who also do not know the correct recovery technique - either that "standard" one or, more importantly, the one described in the flight manual of the type they fly. They are required to have a spin flight activity endorsement so a greater underpinning knowledge and competency. Recently, a flight examiner failed two flight instructor candidates on the ground component of their test because they described dangerously incorrect spin recovery technique in their theory briefing. CASA helped recently with their AC 61-16 Spin avoidance and stall recovery training The FAA's Airplane Flying Handbook, Chapter 5: Maintaining Aircraft Control: Upset Prevention and Recovery Training has excellent information. To go a bit deeper into the subject for much of the underpinning knowledge required by CASA for a spin endorsement I suggest starting with NASA TN D-6575 SUMMARY OF SPIN TECHNOLOGY AS RELATED TO LIGHT I GENERAL-AVIATION AIRPLANES by James Bowman (I worked with Jim for a while). It is engineering stuff however fairly light reading.
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