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-   -   VH-BDS Duchess report released (https://www.pprune.org/pacific-general-aviation-questions/617303-vh-bds-duchess-report-released.html)

Horatio Leafblower 16th Jan 2019 07:31

VH-BDS Duchess report released
 
This is "interesting".
IMHO a few large holes in this report.

ATSB Report Here

oggers 16th Jan 2019 14:18


Originally Posted by Horatio Leafblower (Post 10361853)
This is "interesting".
IMHO a few large holes in this report.

Agreed. Some details that don't stack up:


climbed to a cruising altitude of 7,500 ft in visual meteorological conditions. At about 1816, the pilot slightly reduced power and began descending the aircraft for Cessnock. At about 1821, he felt the aircraft yaw toward the right and observed the right engine indications showing a loss of power...
... an expected freezing level of 7,000 ft....
.... At the time of the engine failure, the aircraft was descending through, and just below, the forecast freezing level
..for those figures to dovetail the pilot would have to have been using 100fpm for his descent. Hmm.

And it goes on, labelling the "approximate conditions at time of engine failure" on the graph at 4 degrees, as opposed to "descending through, and just below, the forecast freezing level".

No reference to a drop in MAP or change of yaw trim that one would expect as a warning sign before the noticeable yaw.

Also in the narrative it is written that the pilot advanced the throttles and props as an immediate action. And yet shortly after it states that he did not select full power on the good engine until after securing the failed engine and subsequently noticing that he could not maintain altitude at Vyse.

And "The ATSB did not conduct an inspection of the propeller feathering system or engine".

All in all, not a great report. Rather cursory as so often with GA accidents.

DeRated 16th Jan 2019 18:55

Some details that don't stack up:

The relevance of a ground level dew point some 6,000+ feet below a moving air mass....... in winter time. Freezing level 7,000 with little or no cloud below cruising level. Normally aspirated engines at 7,500 and reducing power for descent.......!

" Rather cursory ...."

That was kind, oggers.

There is a lot missing here, including the experience levels involved - from the aircraft endorsement to the investigation!

I don't think the disclaimer stacks up:
About this report: Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, a limited-scope, fact-gathering investigation was conducted in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

Horatio Leafblower 16th Jan 2019 23:22

The PIC is a Grade 1 instructor, CFI/HOO, was CFI of Cooranbong for the last 5 years or so, and is a ME IFR Examiner. :D

No examination of engine. No on-site investigation. Just a reassurance from the recovering LAME (was that a mate from Church?) that there was fuel in the tanks.

I know this is a separate question - what action has the regulator taken?

Checklist Charlie 17th Jan 2019 00:16

[QUOTE][what action has the regulator taken?/QUOTE]
Get real, what would they know about flight safety, they are regulators only.
CC

Squawk7700 17th Jan 2019 01:39

Here’s another one that struggled to maintain altitude but they made it back.
https://www.atsb.gov.au/publications...aair200200047/

Horatio Leafblower 17th Jan 2019 02:43

Squark - that's a great report and investigation - better than "they said it was OK so we're pretty sure it was OK"

Judd 17th Jan 2019 09:44

Ever since the first tricycle landing gear fighters came on the scene, research proved it was generally safer to force land with wheels down rather than belly land wheels up. Ditching was different. The RAAF followed this advice with the introduction of the Vampire, Meteor and Sabre jet fighters in the early Fifties. The advantages were energy absorption taken by the landing gear system instead of through the pilots spine as with a wheels up landing. Also with wheels down, brakes are available thereby shortening the landing run. Different with tail wheel aircraft of course where heavy braking on touch down can cause the aircraft to go over on its back.

As with so many flying schools, most instructor school graduates haven't a clue about flying beyond what is taught to them by their own grade three instructors during their early PPL and CPL training. Google might be your friend as they say but very few pilots study flying training history.

In this Duchess accident report, a wonderful opportunity was missed by ATSB to discuss the pros and cons or flight safety advantages of a wheels down forced landings versus wheels up belly landing. A belly landing is fraught with danger on any surface because of lack of energy dissipation and the potential for spinal injury as the shock of impact is directly through the pilots seat to his spine.

Landing gear down on uneven surface may result in one or more landing gears tearing off. But at least in doing so, energy is dissipated that way rather than through the pilots spine at fuselage contact. I believe flying school instructors have a duty of care to inform their students of the facts of the matter.

Capt Fathom 17th Jan 2019 09:56

The issue with landing gear down on an uneven surface is the loss of nose gear. With smaller sized aircraft, like the BE76, there is a risk of nosing over onto your back.
Either way, it’s a gamble. If you’re going to crash, it is likely to hurt.

Judd 17th Jan 2019 11:25


The issue with landing gear down on an uneven surface is the loss of nose gear. With smaller sized aircraft, like the BE76, there is a risk of nosing over onto your back.
Haven't heard of that theory before. Is that personal opinion? Any proven evidence? Maybe any RAAF pilots reading Pprune could advise on RAAF policy on King Airs for example?

Traffic_Is_Er_Was 17th Jan 2019 21:57

Which is probably why the A-10 was designed to leave the wheels partially exposed to lessen the damage when landing with them retracted. Guess the designers didn't listen to the military. Military jet pilots generally have another option rather than landing at all, and that seems to be the overwhelmingly preferred option, leaving the question of gear up or down a moot point.
Gear down would slow the approach speed (which is probably why it was recommended for the early jets), and anything that lessens the energy of the crash that then has to be absorbed by the structure before it is transmitted to the occupants is a good thing.

A37575 17th Jan 2019 22:29


Gear down would slow the approach speed (which is probably why it was recommended for the early jets),
Flaps change an aircraft approach speed - not the landing gear?

Checklist Charlie 17th Jan 2019 23:07

Some Flaps can change an aircraft approach speed by providing low speed lift and/or consequential drag. Extending the landing gear is in most cases, all drag.

CC

megan 18th Jan 2019 00:28

Landing gear down or up? Neither the Dutchess or Baron flight manuals offer guidance on gear position for a forced landing, in fact they make no mention of forced landings, though the Baron manual says to pick smooth sod for a gear up. The C404 manual on the other hand does provide guidance by saying land gear down if the surface is smooth and hard, if the terrain is rough or soft land gear up.

As the incident in question was at night I'd opine the pilot made the correct choice to go gear up, not knowing the precise state of the landing surface. A friend did an engine out in an A36 gear down, day time, into a very good farmers field and tore the nose wheel out when it hit a very small ditch, remained upright with little damage, other than nose wheel and attachment.

Which is probably why the A-10 was designed to leave the wheels partially exposed to lessen the damage when landing with them retracted
Copied the DC-3. :D

The issue with landing gear down on an uneven surface is the loss of nose gear. With smaller sized aircraft, like the BE76, there is a risk of nosing over onto your back
Judd, small aircraft regularly find themselves with their legs in the air, though at inappropriate times. This incident cites braking as the cause, but the nosewheel digging into soft ground can be enough to give the same result, as can landing in standing crops or water. Nor does the King Air manual offer guidance, once again, it makes no mention of forced landings.

https://www.independent.ie/irish-new...-36165824.html


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