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McAero
14th May 2010, 07:36
Hi all,

Just a quick (ish) question.

Are there any specific approvals required for using a laptop in the cabin? Looking to use one as an interface to some test equipment and some eyebrows were raised.

Thanks in advance!

Genghis the Engineer
14th May 2010, 10:08
Hi all,

Just a quick (ish) question.

Are there any specific approvals required for using a laptop in the cabin? Looking to use one as an interface to some test equipment and some eyebrows were raised.

Thanks in advance!

Research aeroplanes do this all the time, although approaches vary significantly.

Where I work (big research jet), we do a tick-box exercise of conforming to the aircraft's main cert basis, but additional points that we include:

- Laptops are built in/on racked instrumentation (securely), or in slide-out trays which are latched in for take-off and landing. In exceptional circumstances, a laptop can work on a lap or spare seat, but again needs stowage for take-off and landing but is less than ideal.

- Removal of all automatic update / internet connection options, periodic external virus checks (probably only relevant to an aircraft with internal ethernet and satcom internet access.)

- If you are operating above a cabin altitude of FL80 or thereabouts, you want solid state hard drives, which have become hard to obtain of late. Otherwise expect developing high unreliability. Fine for anything pressurised, but problematic with unpressurised aircraft.


There is also a concern in some quarters about Li-Ion batteries and their flammability / overheat risks. We don't worry about that on any UK research aircraft that I'm aware of, but the US routinely require removal of batteries from laptops (which presents at that point significant data security issues) on NCAR and I think NASA research aeroplanes.

If perchance you work for or with BAeS at Prestwick, which your profile suggests you do, drop me a PM and I'll point you at some people in your building who have experience in certifying laptops on research aircraft.

G

McAero
14th May 2010, 10:31
Thanks for the reply G.

PM sent.

Pilot DAR
15th May 2010, 12:13
Certainly Genghis' experience confirms mine. I have had hard drive failures climibing unpressurized trough 13,000 feet.

I regularly use small notebooks for data collection while flying. In particular video capture, and vibration information recording. Though some of my subject aircraft do have 110VAC power available, often I am depending upon the internal notebook battery for its operating power. I have noticed that when I am using USB devices in the computers, their battery run time is greatly reduced.

Biggles78
15th May 2010, 17:24
I have noticed that when I am using USB devices in the computers, their battery run time is greatly reduced.
FYI 1. USB Ports will supply 500mA of power so having a USB device connected will reduce battery life. If you run a device that requires 2 USB ports to supply appropriate current (eg: a 100GB USB HDD ), it will be sucking 1 whole AMP. That tends to reduce battery life. High CPU usage also has a similar effect. A larger capacity battery can help overcome a battery that provide insufficient charge life.

FYI 2. NEVER run a laptop from a fabric covered seat. What happens is the cooling air intake vents under the laptop are usually blocked and you get an over heat situation. Put laptop on a flat surface so the "feet" on the bottom of the laptop provide sufficient clearance to enable a proper amount of air circulation to cool the internal workings.

FYI 3. Do not run laptop on your lap if you have the wireless device running. The radiation output for the wireless transmitter can have a detrimental effect on the male reproductive "area" and may cause a lack of children. :sad: It is recommended to have a 2.5 to 3cm space/barrier between the laptop and ones reproductive area. Having the laptop on your lap can also have an effect as per FYI 2.

Hope this provides some useful info for you.

Bear 555
15th May 2010, 17:52
Chaps,

Most of our 'computing' is done on rack-pc's installed and certified as part of the aircraft modification for the trial being conducted.

We do, however, utilise a limited number of 'carry on' laptops running on battery only for specific applications.

Wireless, bluetooth, IR, etc, etc are always disabled.

I'm currently investigating the latest generation of net-books with 'promised' 10hr battery life.


rgrds,

Bear

typhoid
15th May 2010, 21:00
McAero we regularly use laptops on our dev fleet.

We fit them via our FTI team for specific trials work such as EGPWS and environmental.

Those with raised eyes need to get out more :-)

Biggles78
16th May 2010, 14:47
I'm currently investigating the latest generation of net-books with 'promised' 10hr battery life.
Just be aware that the NetBook has a slower, what I would call a "lightweight" CPU but the worse part is the small screen has an equally small screen resolution. A 10.1" screen gives you something like 1280 x 800 if I remember without looking it up. Makes looking at data results on a pain. You can setup a virtual screen but then you need to scroll up, down and sideways to see the whole picture. I would suggest a 14" screen as a minimum on an IBM clone or a 13" on a Mac.

MacBook Pro has a 6 or 7 hour battery.

Milt
16th May 2010, 22:06
Biggles78

What flight testing are you involed in?
How do you connect instrumentation to your computer?
Do we know you in the Flight Test Society of Australia - FTSA?

Biggles78
17th May 2010, 07:13
Not involved in any testing. I usually sit up the pointy end but was forced to take a hiatis as a Network Engineer for a few years. May be able to help with connector advice if your can tell me what connection are on your test gear.

PM me if you want to take this offline.