Pace - as you so rightly highlight, and indeed one of the reasons I was unhappy with some of the earlier posts, it doesnt matter if you think you are a Sky God or even perhaps have the credentials to actually be one, it seems to me even Gods dance on heads of pins when it comes to aviation. If you read the accident reports it is quite extraordinary how many very experienced pilots still make mistakes.

So it doesnt matter why people set off in conditions they shouldnt, and it doesnt matter whether they did because of the chute, in fact none of it really matters because people will always do incredibly stupid things regardless of how much experience they have, and on other occasions it might just not be their lucky day. I guess that is why I find this debate so frustrating. The chutes there for those occasions and better it be there for that, than not, just because there might be the odd person who would never have got themselves into the situation had they not believed the chute would get them out of it.

I still think you will find very very few people look at the weather for example and think to themselves no problem I will pull the chute if I have to. If that is happening it is much more subtle, and much more a case of their believing the Cirrus as a package is more capable than it really is. I just think for any pilot the thought of pulling the chute is actually quite a big deal. In fact there are now sadly quite a number of cases where had the chute been pulled the outcome would almost certainly have been different. That doesnt add up to a willingness to rely on the chute.

Of the cases in which the chute was pulled how many really add to a pilot departing in conditions outside their ability in a way that could have been predicted before they departed? Chute aside statistically how many pilots would still have departed in the same conditions? You really would need some better evidence to pursue your line of argument any further.

Red handle passengers
 

There seems to be an attitude creeping in that the red handle will solve most things when in fact it turns you into a passenger with little control of the surface you are going to land on if the cloud base is low.

I would suggest that an hour of cruising to find a PAR ( under radar guidance following declaring an emergency) is far more likely to calm a pilot down following a big electrical failure and securing the situation than overloading him.

A PAR is likely to be within one hours Cirrus flying time in most parts of Europe and defiantly in the UK, some of you above say you can't find a PAR in the south of the UK but this is untrue Benson and Odiham have PAR for sure, Boscome Down is likely to, the Navy use PAR a lot so try Yeovelton and Culdrose.

Those above who think that SRA is the answer are only half correct because the service terminates at half or two miles, PAR will take you on to the runway so when the weather is very bad PAR is the only answer.

In the end it is down to your skill level, you ether retain control of the aircraft and fly it to a controlled landing or you pull the chute and roll the dice in the hope that you survive the semi-controlled crash that you have initiated.

Fuji

We are really not that far apart ;) How come we are back onto the chute I thought this thread was about saving me money because of my superior skills compared to the normal rabble ;) Only joking I do not have superior skills :ok:

With a twin the second engine is an extra option and with more options come more choices! More choices give you the option to make the wrong choice.

I see the same with the chute capability to pull the chute in all situations is like saying I will climb this aircraft on one engine regardless when it maybe more advisable to pull the live engine back.

Yes you are correct! I am sure I would be embarrassed pulling the chute with the resulting media attention that would occur especially if I came down in an embarrassing place like the middle lane of the M25 on a busy friday evening and landed on top of a school bus :E

So yes there would be a reluctance of making the ultimate failure gesture by pulling the chute.
It may well be the right descision but bar a wing being sliced of by another aircraft or the pilot dropping dead at the controls many pilots would see pulling the chute as the ultimate failure in them and their abilities.

That is slightly different to the presence of the chute instilling false confidence because in the back of your mind there is always the thought that if I ice up too badly I am not totally lost!

If you fitted high explosives to every corner of every car I am sure motorists would drive around with complete caution knowing that if they hit someone else they were dead.

This level of percieved safety is bound to reduce a pilots caution.
That safety is fine if it is respected and not used to cover up a pilots shortcomings.
We had a thread where one poster suggested the VFR on top was fine as the pilot could always use the autopilot to climb himself on top or descend down.
That to me is a very worrying attitude especially knowing how unreliable some autopilots can be.

All these safety advancements are great as long as we treat them with respect and use them as an addition to our skills not to cover up a lack of skills

Pace

The other advantage with a PAR is how little work the pilot has to do.

There is no interpretation to be done. It is an immense reduction in work load. In some ways flying a PAR is easier than flying a visual approach.

I know to those that haven't done one this might sound a ridiculus statement but I am not trying to wind any of you up with this statement.

For all these who want to fly a PAR or SRA in a G1000 Cirrus with blank screens, please remember that the standby AI is powered from two buses: ESS1 and MAIN1. Which also power the PFD and MFD, respectively, so both have probably failed. The standby AI has no internal backup battery!

In fact, the displays are powered from FOUR different buses and both alternators at all times - PFD from ESS1 (both alternators, also BAT2) and MAIN2 (ALT2); MFD from MAIN1 (confusingly ALT2) and MAIN3 (ALT1 and BAT1).

If the standby AI shows the warning flag, which very likely it will, and you are in IMC, it is parachute time.

If you have time to troubleshoot a bit in VMC, you could take out the cat's cradle Cirrus call the electrical system diagram and understand the electrical system, and then isolate the ESS1 bus from the rest of the system by pulling the ESSENTIAL POWER circuit breaker. If that restores power to the AI, great; now you run 1 NAV, 1 COM, PFD, 1 AHRS and the ADC from BAT2 only.

That will last for about 30 minutes (good luck finding that information in flight). So no hour long cruise to the the next PAR controller, thanks.


In an all electrical aircaft, you are relying on the redundancy of the electrical system. While not the best designed, the Cirrus system is quite redundant, so complete failures are extremely unlikely.

NO battery backup? Seems a bit silly for a IFR machine.

How are the buses organised?

No built in battery backup, I should have written.

The point is, if all four PFD and MFD power sources have failed, the power sources for the standby AI will also have failed. Ultimately, it is powered by both alternators and both batteries, so very redundant to begin with.

In a power related failure, you are less likely to lose both PFD and MFD than losing the standby AI.



If you want more detail, read on:


Distribution buses:

• MAIN DIST 1 is powered by ALT1 and BAT1.
• MAIN DIST 2 is powered by ALT2, and automatically from MAIN DIST 1 (via a diode) if ALT2 fails (no cross-tie relay, so it only works one way, if you lose MAIN DIST 1 it is gone for good).
• ESS DIST is powered via diodes from MAIN DIST1, MAIN DIST 2, and BAT1.
• ESS DIST is also powered directly by BAT2 (through a slightly confusing path via the ESS1 bus)

Circuit breaker buses:

• The standby AI is connected to ESS1, which is powered by ESS DIST and directly by BAT2
• It is also powered by MAIN1, which confusingly is powered by MAIN DIST 2

So overall, it gets power from all four power sources.

Any electrics involved with deploying the chute?

No electrics involved with chute deployment.m

Seems a bit daft not having a couple of kg's of nicads as a backup for the standby AH.

What are the main bat's, nicads or lead acid?

Do they stagger the alternator maint or do you usually replace/overhaul both at the same time?

Personally with that set up I would be wanting one alt that was half lifed and one new both from different batches.

Unfortunately there isn't a easy solution to the fact that the alternators both have a common earth which means if one goes if can back spike the earth and take the other one out.

I suppose if you were that bothered, you could swap the AI for one with integrated battery backup - they are fairly common now. With all the redundancy offered by dual everything else, it's probably not necessary?

All the batteries are sealed lead acid.

The two alternators are different. They have different output ratings, as well as the fact that one is belt driven and the other direct drive. I guess given all that, they are also unlikely to be from the same batch. I didn't think alternators were lifed components anyway? Don't you just check the brush assemblies at the annual?

Well ultimately, everything has a common earth doesn't it!

For me it would be worth it. Main because if i had that I would be happy without the rest

Your aircraft earth isn't really an earth its just zero PD compated to the supply the actaul aircraft can be way above zero relative to the "earth" in rotorary and a quite a bit less for fixed wing. You do get protected earth buses for some essential system in bigger things.

As for the life items yours might not be, some are. British designs tend to be lifed items. Even if they would be on inspection under other authorities. Cessna seem to be going the same way though these days.

Outside the aircraft world engineering if you have two system which do a job its always worth having an age /cycle split between the systems because things tend to wear out at the same rates unless you stick in a sacraficial adjustor to make sure one fails before the other.