aeroplane controls

[Panzer Vor!!!]

On a recent trip to a museum we look inside a cockpit of a twin engine airliner .I was wondering how many instruments you need to fly a plane sefely and land it?? So the question is

How many instruments to fly a plane safely and land if you lose instruments in mid flight ??

Checked for sexist comments none found

[Test Graham]

There used to be a "basic six" arranged in a T on RAF aircraft, but I don't recall all of them. The one really vital one is airspeed, assuming clear air visibility unlimited. Radio is useful to warn the crash team and encourage everyone else to keep clear. Current pilots may wish to add......

[Shar2]

Working on what the emergency busbar supplies on our Learjet I would say

Airspeed

Altitude

Vertical speed indicator

Attitude indicator not strictly necessary in VFR

Radio

[Panzer Vor!!!]

i see six? we got it to five..........

Radio

Altimeter

Airspeed

Artifcal horizon

and ii cant remeber what we said for the fifth

oh yes fuel gauge

[StephenMG]

The basic six in older RAF aircraft used to be contained in the "Blind Flying Panel" - that's the separate panel you see in the middle of, say, a Spitfire instrument panel. It was a standard unit (with the slight variation of a curved top type and a rectangular type) fitted to just about all RAF aircraft. It contained the basic instruments needed for blind flying - hence the name! They were, clockwise from top left, airspeed indicator, artificial horizon, rate of climb indicator, turn and slip indicator, direction indicator and altimeter. See a photo of mine here http://www.gbairspares.co.uk/reference/bfp.htm.

Mark

There used to be a "basic six" arranged in a T on RAF aircraft, but I don't recall all of them.

[Panzer Vor!!!]

but are these the basic for ALL aircraft would they suffice for a A380?????

[xffw45343tg]

I should know from my PPL Air Law exam (I'm afraid I'm not 100%) but I think the essentials for Visual Flight Rules flight are even fewer and something like:

• Pressure altimeter
• Airspeed indicator
• Magnetic compass
• Timepiece

Kirk

PS/ No, you couldn't land an A380 like this.

Edited March 28, 2013 by Kirk

[Test Graham]

It's only a bit bigger - the pilot just flies his seat and the rest tags along. (Comment credited to Bill Pegg and the Brabazon, but I dare say much the same sentiment has been expressed many times since 1903.) If you've lost your screens but everything else on the aircraft is working, in CAVU and not a long way from an airfield, that's all you need. If you have to do fuel balancing, then you will have problems, but just how many failures are you throwing at this poor guy?

[Iain Ogilvie]

If we're talking absolute basics - and flying VFR - Mk 1 eyeball

As a lowly PPL stude on single piston engined spam cans my instructor taught me to look out as much as possible - only using the inward glances at instruments as confirmation of what I was seeing, hearing and feeling. Try to get a 'feel' for the aeroplane...

• Position of horizon relative to nose/windshield - you get used to this for different aircraft types (pitch - airspeed)
• Engine 'sound' - you get used to what the engine should sound like at max power/cruise/idle (power- climb/descend)
• Feel of controls (obviously not if hydraulically boosted/FBW!) - slower you get the mushier the feel (airspeed) Obvioulsy there's the feel as you approach the stall at the very bottom end - something practiced regularly - especially when flying a new type.

Others will be along with vastly more experience - I have absolutely no experience of anything relatively high performance - but using the above I could land the aeroplane with no instruments... I think

Iain

[Panzer Vor!!!]

All the pilot has is the basics no autopilot , no computers, nothing he might as well be flying a 1912 aeroplane

[xffw45343tg]

Radio not strictly necessary. High on a list of "nice to haves".

AI is handy, but if you've got windows...

VSI? Really? Altimeter + watch should see you right.

Shouldn't need a fuel gauge except if you have a leak. You calculated before you set off, right?

Not an instrument but you'd really want a chart in that kind of situation. It's obligatory in any case so should be to hand.

[xffw45343tg]

If we're talking absolute basics - and flying VFR - Mk 1 eyeball

As a lowly PPL stude on single piston engined spam cans my instructor taught me to look out as much as possible - only using the inward glances at instruments as confirmation of what I was seeing, hearing and feeling. Try to get a 'feel' for the aeroplane...

• Position of horizon relative to nose/windshield - you get used to this for different aircraft types (pitch - airspeed)
• Engine 'sound' - you get used to what the engine should sound like at max power/cruise/idle (power- climb/descend)
• Feel of controls (obviously not if hydraulically boosted/FBW!) - slower you get the mushier the feel (airspeed) Obvioulsy there's the feel as you approach the stall at the very bottom end - something practiced regularly - especially when flying a new type.

Others will be along with vastly more experience - I have absolutely no experience of anything relatively high performance - but using the above I could land the aeroplane with no instruments... I think

Iain

Don't even need an engine to get it on the ground - and I'm assured you can steer a Cessna with the doors if you break the primary flying controls. Would be nice to have a bit of flap though..

[Iain Ogilvie]

Don't even need an engine to get it on the ground - and I'm assured you can steer a Cessna with the doors if you break the primary flying controls.

Indeedy - have heard tel of this being tried!

And - yes to no engine - the joys of PFLs and glide approaches

Iain

[xffw45343tg]

Indeedy - have heard tel of this being tried!

And - yes to no engine - the joys of PFLs and glide approaches

Iain

Indeed. What's up checks:

Carb heat: HOT

Fuel: ON

Mixture: FULL RICH

Throttle: "Some eejit's closed the blooming throttle. Ah that's better." (I'm told that examiners don't find this funny, so I didn't try it!!)

[Iain Ogilvie]

Throttle: "Some eejit's closed the blooming throttle. Ah that's better." (I'm told that examiners don't find this funny, so I didn't try it!!)

LOL - I did that with my instructor a couple of times - just to check she was paying attention of course! Usually resulted in a slap and closing the throttle again...

It's the practice EFATO's that really get you

Iain

[Vickers McFunbus]

If we're talking absolute basics - and flying VFR - Mk 1 eyeball

Yep. One of either Manifold pressure, RPM or Air Speed would be nice for landing, but actually, not very much is needed.

[Aeronut]

If we're talking absolute basics - and flying VFR - Mk 1 eyeball

I concur, I'd also add that speed is judged by the attitude of the nose in relation to the horizon backed up by the wind noise (quiet = too slow, Very loud = too fast). I've even carried out PFLs pretending to have a jammed control column leaving me with just rudder pedals and elevator trim.

[Test Graham]

OK for private flying but the question was about airliners. The pilots don't hear the wind. You can't judge the speed from the pitch angle wthout power setting and rate of climb/descent.

[xffw45343tg]

I think the problem is that the "right" answer depends on all sorts of factors:

• Which aircraft?
• What altitude?
• Day or night?
• Where?
• etc

A well-trained crew could probably put an A380 down with a high percentage of survivors without ANY instruments provided they retained flying controls and had a nice big flat dry salt lake bed. The result at night in mountains in a thunderstorm would be somewhat less happy.

How many instruments? As many as are still working please.

Edited March 28, 2013 by Kirk

[Vickers McFunbus]

OK for private flying but the question was about airliners. The pilots don't hear the wind. You can't judge the speed from the pitch angle wthout power setting and rate of climb/descent.

Air speed indicator then. Engine instruments would make it easier, but not essential.

[bentwaters81tfw]

I recall many years ago when PPL training that instrument flying consisted of the instructor progressivly sticking cardboard over the instruments until only the turn and bank was visible.

Yes...Mk.1 eyeball convert what you see outside the plane to the maps, not vice versa.

Also if the altimeter fails due to blockage, ice etc, break the glass, and it then will read, but in reverse!

Yes, A Cessna was flown by 2 experienced pilots who inserted the control lock at altitude, and landed the a/c on throttle and opening the doors.

[stringbag]

Air speed indicator then. Engine instruments would make it easier, but not essential.

I'm so glad someone has finally put this one at the top of the list.

all others I would consider as handy additions, but airspeed is crucial.

[Vickers McFunbus]

I'm so glad someone has finally put this one at the top of the list.

all others I would consider as handy additions, but airspeed is crucial.

With a large aircraft, with the variations in weight etc, the approach and landing speed will vary, so really the ASI is a must.

In a light aircraft, the difference is minimal, so one of the ASI or the "power" instrument(s) would be desirable.

Edited March 29, 2013 by Vickers McFunbus

[melvyn hiscock]

It would depend on the airliner but if you have lost instruments on many you may well have lost the controls too!. Al Haines, who flew the Sioux City DC10 nearly landed that with just differential power. It was the crosswind that caused the wing to drop as they landed. He had instruments though. A 747 captain friend once told me they need angle of attack so they can judge the drag and airspeed. On light aircraft it is suprising how much you can judge. I flew a check ride in my Rearwin and had the ASI covered. Then the most important control was RPM. Even then I was not using it on the approach, the trim position and rate of descent was relatively easy to judge and according to the check pilot,. who was looking at the ASI, I had it pegged on the right speed but I did have about 500 hours on type.

[Plastic Bonsai]

You can just have one instrument like this one: http://www.meggitt-avionics.co.uk/products/flight_displays/isfd.aspx

Designed to work off a battery bus for when all the other electronic displays go out. There's enough data to recover the aircraft and land it in IMC if you have an ILS receiver fitted.

Edited March 31, 2013 by Plastic Bonsai