Police helicopter crashes onto Glasgow pub

[henry_crun]

I think there was difficulty switching between nvg exterior vison and 'under the goggles' interior vision. This could have been compounded by that eyesight defect known as 'lack of accommodation' which is difficulty in focussing near-and-far which as those of us over fifty years old know creeps in gradually and finally locks us into fixed-focus machines. A few lucky people, myself included, have different focal lengths in the two eyes, but for most folk the fls are the same for both eyes and lack of accommodation hits unexpectedly hard. In a helicopter nvg situation, corrective spectacles would have to be very cunningly designed to be of assistance.

[helmet fire]

Forget NVG as nothing more than a convenient whipping boy. The colours and displays are generally better in NVG equipped acft than non equipped. The EC135 has a great NVG cockpit. If you want to find out more about goggle settings and colours and look around, there are NVG threads that discuss this in detail - and really don't need to be repeated in the midst of this already repetitive thread.

Falcon- I think there are several more possibilities.

TCF: is there any reason in flight to have turned a serviceable transfer pump off in the EC135?

[MightyGem]

I am asking if pilots are aware, as general knowledge, that a significant amount of fuel is unusable in the main, if the transfer pumps are not working.

Possibly, possibly not. I don't remember it being mentioned on our ground school. Certainly the FLM makes no mention of unusable fuel after a double Transfer Pump failure: only Single Pump failures. It was only after I flew with the Transfer Pumps off, to see what would happen, that we knew that as much as 255kgs would be unusable in the main tank.

[Art of flight]

As MG points out, there is no mention in the RFM of a specific quantity of unuseable fuel after both xfer pumps are failed/off, simply because the manufacturer can't possibly know when they might both fail. Therefore they specify the expected amount that can't be transfered when one fails and this qty is dependent on which one and flight conditions as specified in the RFM.

It would seem to be general logic that if pumps are required to move fluid from one tank to another by design, and all the pumps stop working, no more fluid can be moved, thereby leaving that fluid in that tank. What worries me is a case of a 135 aircraft being operationally able to dispatch (in line with the MEL) with only one serviceable xfer pump, in that case I would be very cautious about operating near the endurance of the fuel in the supply tanks...ie...if the remaining xfer pump stops now, can I reach fuel, or execute a safe landing with what is in the (full) supply tanks.

I agree that the NVG cockpit lighting in the 135T2/P2 is very good, it produces a good range of muted colours, ie the fuel graphic is still blue, the cautions are yellow etc, they even changed the very annoying orange High Nr light to a very annoying green light! One mod might be to replace the hard to find dimmer up/down push sensitive rheostats with old fashioned knob. Once you've dimmed the instrument lights it can be hard to locate the finger tip sized panels to adjust it again. But again, it's a matter of living with it.

[skadi]

What worries me is a case of a 135 aircraft being operationally able to
dispatch (in line with the MEL) with only one serviceable xfer pump, in that
case I would be very cautious about operating near the endurance of the fuel in
the supply tanks...ie...if the remaining xfer pump stops now, can I reach fuel,
or execute a safe landing with what is in the (full) supply tanks.

Our MEL with one XFER pump U/S dispatch is only possible VFR and safe landing must be possible within 15 minutes on each phase of the planned flight. That makes sense.


skadi

[rantanplane]

How far can the instrument lights and info panels be dimmed down?
If the CAD was dimmed down for NVG use but the pilot was not using them any longer when flying over the well illuminated city, forgot to bring the instrument lights up again, could it be possible to miss out info from the CAD and/or other panels as they are just not bright enough? (sorry if that has been asked before, not aware it has)

[AlphaZuluRomeo]

rantanplane, as demonstrated by SS's videos, the MASTER CAUTION also illuminates.
The MASTER CAUTION is not on the CAD, but separate (next to the red warnings panels).
If the CAD is too much dimmed to be read, the MASTER CAUTION would attract your attention (which is just its purpose btw).

[rantanplane]

Thanks, not sure if Sid's videos were specifically about 'dimming'? I read the CAD was switched off, a bit different situation I guess, maybe I have missed s.th. The reaction to the red master caution is the big miracle (for me); one detail that concerns me is the recording of first 'intermittent' LOW FUEL 1 master caution before they became permanent LOW FUEL 1 and LOW FUEL 2. The pilot might have been distracted by an intermittent warning? and was perhaps acting not pessimistic or assertive enough, not calculating to land in 10 min from the very first flash of the master caution. And then base was already very close.

[Art of flight]

"Our MEL with one XFER pump U/S dispatch is only possible VFR and safe landing must be possible within 15 minutes on each phase of the planned flight. That makes sense."

Yes, it does make sense, just not a very practical situation for a police aircraft at night tasked to far flung (and fuel-less counties). All UK police flying is VFR, day and night as there is no requirement for flight in IMC.

[AlphaZuluRomeo]

rantanplane, you're mixing things up...

Your question was (as I understood it): "what if the pilot didn't see the cautions on the CAD because the CAD was dimmed?"

My answer is: "when a caution appears on the CAD, you also get the "MASTER CAUTION" illuminated. This is not part of the CAD display, hence it won't be dimmed when you dim the CAD.
This has nothing to do with the red warnings and/or the associated 10' endurance.

And there is no such thing as a "red master caution". There are warnings, there are cautions, and there is a MASTER CAUTION light. The latter illuminate for a (red) warning or for an (amber) caution.

[skadi]

just not a very practical situation for a police aircraft at night tasked to
far flung (and fuel-less counties).

Indeed, not practical, but according MEL such a task would be a nogo at night with one pump U/S.

skadi

[rantanplane]

AZR, I am mixed up..
again thanks for the info, so far I had the understanding the master caution does not illuminate with every caution on the CAD.

[SilsoeSid]

rantanplane

AZR, I am mixed up..
again thanks for the info, so far I had the understanding the master caution does not illuminate with every caution on the CAD.

As in the flight manual that has been linked to loads;

WARNINGS AND CAUTIONS
Emergency situations will be indicated either by a red warning light on the WARNING PANEL coming on together with a gong signal, or a caution indication on the CAD and a yellow master caution light on the instrument panel.

A red warning light indicates a hazard which may require immediate corrective action.

A yellow caution indicates the possible need for future corrective action.

The cautions, indicated at the CAD, are divided into three sections, SYSTEM I, MISC and SYSTEM II. SYSTEM I indicates the operating conditions of the left power plant or the system 1 of a redundant system. SYSTEM II provides the same features for the right power plant or the system 2 of a redundant system. MISC indicates the operating condi- tions of the non-redundant systems.
The yellow master caution light in the pilot’s field of view leads the pilot’s attention to the indication(s) on the CAD whenever a caution has been activated there.

Each caution (CAD-indication and master caution light) must be acknowledged by the pilot (copilot) by pushing the CDS/AUDIO RES button on the cyclic stick grip or the SE- LECT key on the CAD. Acknowledged cautions are indicated in sequence of arrival. In case of lack of space on the screen, further confirmed cautions will be stored on addition- al pages, which will be indicated by the “1 of 2” message on top of the middle column. They can be called up via the SCROLL key. Any new unconfirmed caution overlies the previous caution and is bordered by two flashing lines to draw the pilot’s attention to the new caution.
It is always possible that a warning light or caution indication will come on unnecessarily. Whenever possible, check the light or indication against its associated instrument to verify that an emergency condition has actually occurred.

[SilsoeSid]

...and to show y'all the cockpit/CPDS setup;

https://translate.google.co.uk/trans...bertechnik.htm

[henry_crun]

Sid, thanks ever so much, that's really helpful, henry

[tigerfish]

But remember this was a Police Machine so all of the Instruments/controls infront of the left hand (Co pilots) seat would not be there, and would have been replaced by a fairly large TV screen or monitor on which the FLIR, and daylight camera pictures would be displayed and the controls for other Police mission equipment.

The accident machine was a fairly recent version, so probably fitted with digital displays instead of analogue guages.
TF

[rantanplane]

thanks Sid, I'll take the yellow master caution as per your post 2409.
Sometimes I'm a bit archaic and need to feel, smell and taste to believe and realise, or at least have a picture in front of me..


last week some of the pages have not been accessible for me for some reason?

[Reely340]

...and to show y'all the cockpit/CPDS setup;

https://translate.google.co.uk/trans...bertechnik.htm

Yikes! where is the long row of separate red warning lights?
I expected a good dozen of real, old style, filament driven, red warning lights on the very top end of the shrouded instrument panel, so that them lighting up would be noticable via peripheral vision even when looking out front.

Something similar to the topmost row of ~15 squares as seen here http://i1.ytimg.com/vi/9Be6cx9J0-s/maxresdefault.jpg

My impression was that the yellow caution "lights" are done via screen display, with only the master caution being a real light / pushbutton (to aknowlegde the caution) but that all red warning lights were still implemented as separate, old style lights. Thus should the fancy screens malfunction or turn black ("only" serving caution lights at best anyhow) the red warning lights would still function, being a totally different, screen-independent (=old stlye) set of individual lights.

edit: I think I found the red lights, they are at the empty black areas, near the illuminated "Rotor RPM" red warning. I was searching for press-to-test type light sockets of a last milennium type S300C, my bad. I'm defnitely not fully awake yet.

[SilsoeSid]

Yikes! where is the long row of separate red warning lights?

See posts 2602 & 2614

[mickjoebill]

and would have been replaced by a fairly large TV screen or monitor on which the FLIR, and daylight camera pictures would be displayed

Probably not relevant to the thread, what controls or monitor hoods are used during night flights to maintain a viewable image on the monitor for the observer that also prevent the pilots NVGs from blowing out?


Mickjoebill