Cirrus SR22 crashes at Zürich (LSZH)

[koni]

A Cirrus SR22 crashed at LSZH yesterday afternoon. Weather was a factor: LSZH 221150Z 31008KT 2500 -DZ FEW002 SCT007 BKN011 08/07 Q1020 NOSIG

News link (in German): http://www.nzz.ch/nachrichten/zuerich/zwei_tote_und_zwei_schwerverletzte_bei_flugzeugabsturz_in_kloten_1.1153117.html


Here is the ATC recording.  LSZH2-Oct-22-2008-1330Z



relevant recording start 18:42

18:42 (Laufzeit File LSZH2-Oct-22-2008-1330Z.mp3)
N-BD reports"reduce 6000, ft with speed 140"

19:20
Final: "turn right HDG 230, short donwwind leg"

19:28
Final: "N-7BD, descent to 5000 ft"

21:10
Final "N-7BD, turn LEFT HDG 230"
??

21:16
ATC asks if 160 can be maintained on the ILS
then "maintain 140 for the time..."

22.18
N-BD cleared for ILS 14

25:10
N-BD: "established, BD"

25:11
Final: "report your altitude"
N-BD "3300, HDG 144"
Final: "you seem to be a little bit right of the LLZ and able to continue?"
N-BD: "OK- we can cont. on the current HDG for the time being"

25:33
Final: "report your ALT now"
N-BD: "3300 ft"
Final: "and you have the GS signal?"
N-BD: "no. negative. no GS signal"
Final: "present HDG, climb 6000 ft"

26:15
ATC asks for altitute
N-BD reports PWR failure and Requests  VFR
Final: "maintain vis. GND contact, HDG 140. keep the tracking to the field"

26:53
Final: "twelve o clock pos., range two miles"

27:40 Final: …16, you’re approaching now the intersection between RWY 16 and 28
N4567BD: … we do a 180 and approach the RWY 14?
27:51 Final: Confirm you have still visual GND contact?
N4567BD: We have still and we have RWY in sight, BD
27:56 Final: N7BD contact TWR 118.1 for further instructions.
28:20 N4567BD: …RWY14, BD
28:26 TWR: BD, do you have RWY in sight?

no more contact after that.  Then airliners are instructed to hold over  KLO, GIPOL,...

LSZH2-Oct-22-2008-1400Z
shows how ATC handles the remaining incoming traffic (great work from ATC)

[Lotna]

Does anyone know how to interpret the last conversation starting at 27:40?

[Heading090]

In my view it indicates that he was already too far to land on runway 14, i.e. over the airport (over the intersection of runways 16 and 28) which means he was quite a bit to the west of runway 14.
Then, he wants to make "a 180" (i.e. a 180 degree turn), presumably to return to runway 14 to try again.
The terrain around Kloten is not a joke but in this case it is difficult to say (for now) whether it was a "controlled flight into terrain" or the crash can be attributed to problems he had reported.

[SH521018]

Your assesment is correct. Marius and his passengers were all my friends and will be greatly missed. Electrical failure rendered the airspeed, altimeter, and turn and bank unusable. His air speed dropped in the 180 Deg and he spun out of the turn from 3600 feet. 

[Lotna]

Is it possible in emergency cases like this for ATC to give specific instructions and directions to help pilot to land on the runway? In case of N-BD is seems like ATC waited too long before notifying the pilot he had missed the runway.

[schoedl]

The SR22 G2, like the G1 I fly, has two alternators, a large one powering the "main" bus, which powers everything, and a small one powering the "essential" bus. When losing the small one, pretty much everything still works. If the large one is gone, you lose some equipment, but PFD and one GNS430 should still work, so flying an ILS should still be possible. Is it already clear what was happening in this case? Did both alternators die?

[KSYR-pjr]

Electrical failure rendered the airspeed, altimeter, and turn and bank unusable.

My condolences for your losses.  This must be terribly difficult for you and other family and friends of the accident victims.

For the "glass cockpit' Cirrus panels, Cirrus provides a backup altimeter, airspeed indicator, and artificial horizon/attitude indicator gauges in the event the primary flight display fails.   The airspeed and altimeter instruments are driven solely by air pressure (whether it be ram air pressure or static air).  The gyro behind the AI could be driven either by electricity or vacuum pump (I don't know what Cirrus chose to use).   Were you referring to these backup instruments or were you referring to the primary flight display in the comment quoted above?  

[schoedl]

The SR22 AI is electric, at least in the non-glass SR22 G1. I am pretty sure the backup gauges in the G2 are electric as well.

[KSYR-pjr]

The SR22 AI is electric, at least in the non-glass SR22 G1. I am pretty sure the backup gauges in the G2 are electric as well.

You are using the plural of gauge so I am confused.  Are you stating that all three backup gauges are electric?

[schoedl]

Sorry, I meant singular, just the AI. Speed and altitude are pressure-driven of course. Speaking of which, was ice a factor? I was flying the same day from Berlin to Duesseldorf, and freezing level was at FL50 in that cold front.

[KSYR-pjr]

Speaking of which, was ice a factor? I was flying the same day from Berlin to Duesseldorf, and freezing level was at FL50 in that cold front.

It depends - what is the field elevation of the accident airport?  If the airport elevation were at least 1,000 feet below the freezing level from that day,  then most likely icing was not a factor. 

I can tell you from experience that an aircraft covered in ice will begin shedding ice the moment the aircraft reaches temperatures even one degree above freezing.  It doesn't take long thereafter for the aircraft to be completely free of ice, assuming no freezing rain and that the aircraft remains in air temperatures above freezing.

[schoedl]

A poster talked about a spin from 3600 ft. Pitot ice may form even at temperatures above freezing, and would render the airspeed inop. Just speculating, I guess we should wait for the formal investigation result.

Accidents like that always give me a good scare. I just reviewed the SR22 electrical system for the time when it is my turn to lose an alternator...

[KSYR-pjr]

Pitot ice may form even at temperatures above freezing, and would render the airspeed inop.

I respectfully disagree.  In my experience of flying downwind of the US Great Lakes just about twice every week for six ice seasons now, pitot ice forms when there is visible moisture and air temps at or below freezing.  Visible moisture would be in the form of a cloud, freezing fog, freezing rain, or very wet snow that may clog the opening.  

If pitot ice were to form above freezing (which would also mean that the airframe were picking up ice), I would cast a suspicious eye on the calibration of the outside air temperature probe.

Of course airframe/pitot icing should not to be confused with carb ice, which can and does form in temps way above freezing, but for those of us who fly with an engine equipped with fuel-injection this is not an issue.

For more on icing the US organization, AOPA, puts out a good Air Safety flier on icing, found here:

http://www.aopa.org/asf/publications/advisors.html#sa11

[schoedl]

I guess you are right, pitot tubes provide ram air pressure after all, so temperature and pressure are slightly above the environmental temperature/pressure. I must admit, I have no experience with pitot ice, and only very little with airframe ice.