[as the] Radar Sweeps

When Ellen and I flew the last really long cross-country in 11D two years ago we decided that we wanted to add two capabilities before the next long one: onboard traffic and satellite weather. Well, we are about to leave for the next truly cross-country adventure - California to Connecticut - and I’m happy to report I have taken care of one of the two items: weather. Selecting a system from all the available possibilities and actually getting everything the way I want it has been a bit of a saga…

GlassView running on the tPad 800, attached to a Dell M65 behind the co-pilot seat

Certified or Portable?

Today, there are a lot of options for getting weather into the cockpit. I already have a Garmin GNS430W. Without question the simplest solution would have been just to add a GDL69 and display the weather on the 430. It costs about $5,000 installed and you get a reliable, certified solution, which has it’s advantages - it’s from a single vendor, no integration hassles, very well tested. I considered this route, but I don’t think it is optimal. First, the size of the display is a disadvantage - there just isn’t much there, there. Second, the controls are [IMHO] not well-adapted for, for example, selecting an airport and displaying it’s METAR [push cursor, scroll up/down, scroll left/right to airport, Enter, twist knob to METAR page]; that is a bit of work. Lastly, I don’t like the increased dependency on a single device - what happens if that device [or my avionics master switch, or the circuit breaker, or both generators!] fails? No GPS, no map, no weather. If, for the same money, I could build in some redundancy I would feel better about the result. I decided to look further [and since the Garmin 396/496, as good as they are, suffer from the both the 1st and 2nd issues above I’m going to dismiss them right now].

Which Software Moving Map Package? Voyager GlassView Shines

There are multiple ways to get XM Wx with a direct input [touchscreen] display - AnywhereMap being a good example. It gets good reviews, is reasonably priced, and was has been around long enough to have shaken the bad stuff out. Both the GPS and XM Wx receivers connect to a PDA or larger device via bluetooth, eliminating some wires [almost always a good thing]. But as I proceeded down this path I decided to look at what Seattle Avionics Voyager, my chosen flight-planning solution, had to offer. They sell an add-on module to Voyager, GlassView, that is intended for inflight use: GPS moving map display, support for XM Wx and lots of other capabilities. It proved to be a very capable product that, especially when I took into account my reliance on Voyager for the ground-based planning phase, is compelling as an inflight monitoring tool.

What Kind of Hardware?

With the software decision made, it now became a question of what to run GlassView on. Recognizing that integration is a major pain, Seattle Avionics sells turnkey systems - hardware with their software already installed. I first went to my local electronics store and played with one of the devices they sell - a Samsung Q1. The size is better than your typical PDA or the 430, but I just can’t see looking at an Instrument Approach Plate[IAP] on this thing and, while this was not a critical capability right now, I wanted to keep that option open.

Next largest device is a tablet computer, like the Motion Computing LS800. From a form-factor standpoint I think this is close to perfect - large enough to really see things and to large enough to manipulate - there is literally going to be a lot of finger-pointing with a touchscreen and it needs space, particularly in a bouncy cockpit environment; it is also small enough to actually fit somewhere in the cockpit.

But the horsepower of the LS800 [or its big brother the LE1700] is limited. I didn’t like the idea of a clockspeed of only 1.2GHz. My desktop machine is 2GHz and I didn’t want to give up performance in the airplane, I wanted to improve it!

Voyager [a .NET application] consumes a fair amount of resources and the addition of XM Wx would only add to that load. I was really looking to throw as much CPU and RAM at this task as I could.

So what about decoupling the display from the computer and getting a more capable computer? Well, navAero has done just that: they have a developed a special-purpose computer and integrated that with a high quality, daylight-visible display, calling it the t-Bag C2² Electronic Flight Bag [EFB]. But…the maximum amount of RAM it can hold [as of April, 2007] is 1GB and the fastest CPU available is 1.8GHz. And to get the system with these upgrades the list price climbs out of sight to $7,685. Clearly, aimed more at air carriers, and other commercial operators, not general aviation.

But they do sell the display separately: the tPad 800 is an 800×600 resolution touchscreen large enough to see and touch, and works with any computer with VGA out. So…I decided to “integrate” my own system.

So, What Exactly is the Goal?

Here are the hard [non-negotiable] requirements:

• Ability to display XM Weather on a moving map;
• Ability to refresh display quickly [fast clockspeed, lots of RAM];
• Ability to keep running, regardless of altitude [solid-state drive];
• Power
  • Ability to run independently of airplane’s power [before start or after electrical failure], but benefit from it when available;
  • Minimum 6 hours battery life;
• Removable from airplane for use as laptop while on the road, for easy updates, in-hotel flight planning, etc.;

Soft requirements [nice to have, but not required]:

• Integration with flight planning software;
• Ability to display IAPs;
• Ability to incorporate an IAP into the moving map [geo-referencing];
• Completely seamless operation;

My Solution

The Laptop

The fastest laptop I could find at a reasonable price was a Dell M65 Precision Workstation from their outlet store. The outlet sells units with cosmetic damage, refurbished returns, and machines that were ordered but never shipped. I have purchased a lot of boxes from the Dell outlet over the years and have been very satisfied. The stock varies almost by the minute, so if you don’t like what you see come back a little later. I got a 2.33GHz Core 2 Duo with 1GB of RAM and a 60GB hard drive.

The first modification was to replace the two 512MB sticks of RAM with two 2GB sticks, for a total of 4GB. Windows XP only sees 3.25GB of this, but hey, it’s that’s way better than 2GB.

The Storage

I have read multiple reports of hard drive failures at around 9,000′ so the next task was replacing the hard disk with a solid-state drive. The Windows XP operating system and other applications were already occupying close to 8GB already so I got a 16GB drive. These are not cheap and the one I could afford is not particularly fast. So I added a 2nd solid-state disk, in the form of an 8GB Lexar ExpressCard [ECs are a new form-factor of expansion card, like PCMCIA cards]; this is substantially faster than the new C:\ drive and is for the Voyager install, with all its data. Here is the performance data for the all three drives:

The Seagate [old 60GB rotating hard drive]

The Super Talent [new 16GB C:\ solid-state drive]

The Lexar 8GB ExpressCard [new E:\ drive]

The Seagate shows the best transfer rate, but the worst access time; performance is the result of both. The access times of the flash drives are the yellow dots at the bottom of the graphs ;>)

Power

While the runtime of the laptop’s primary 85WH battery is extended substantially by removing the rotating hard drive, I just don’t ever want to find myself saying, “!^&%, out of battery!”. So when the Dell is in the plane it is plugged into a Valence N-Charge battery. This should result in something like a 10-hour runtime capability. The N-Charge comes with two cables, one designed insert itself between the Dell power adapter and the laptop, and one with a standard cigarette lighter adapter [CLA]. I’m using the CLA to power the tPad 800 display. The N-Charge Dell cable is plugged into a Lind power adapter [also designed for the Dell], which, in turn plugs into the a 28V CLA in the airplane.

Mounting

The tPad 800 is mounted on a gooseneck, ball-joint, and bracket assembly from RAM, which I have placed between pilot and co-pilot. The gooseneck makes it easy to adjust and there is plenty of room between the seats and aft of the power quadrant.  Since I didn’t want to go through a field approval, the whole system is independent of [not attached to] the airplane, except for the connection to a CLA.

The tPad display gets its signal from a control box. That box and the XM Wx receiver are mounted under the co-pilot seat. Then on the floor between the co-pilot seat and the middle seat is a mount for the battery and the laptop.

The Result

While not cheap [in toto, the cost is almost identical to the GDL69], it is highly functional. All of my hard requirements are met, and most of my soft ones as well. In addition, should anything happen to the 430, I have another moving map, which may someday prove to be handy [there are plenty of pilots out there who have a Garmin ?96 in addition to their 430 for this very reason].

There is some inconvenience with the current setup: unlike a Garmin GDL69 solution, [assuming I removed the laptop after the last flight] I need to connect a few cables [video out, touchscreen data-in, laptop power, N-Charge power, mousepen and keyboard [yes, I have one that sits in the co-pilot seat-back pocket just in case], power up the laptop, and then slip it into its mount. This whole operation takes me about 3 minutes right now and should get faster. It seems well worth the benefits gained. But with the essentially unlimited battery life I can do this before pre-flight, before passenger loading, before fueling - whenever it is convenient - and just leave it on through the rest of pre-flight preparation.

An unexpected benefit is the new support in the 3.6 version of GlassView for fuel pricing from 100LL.COM; I expect this to come in very handy on this upcoming trip. The photo below show a simulated flight, over KTNP with fuel prices on the chart and the “Nearest” list at the bottom of the screen is sorted by fuel price. Note also that where reported wx is available, it is displayed. Big Bear, Barstow-Daggett, and Blythe are reporting VFR.

So far I only have a short flight with the system and it seems to work very well. I will provide updates as I have them.

Safe Flying!

ak

This entry was posted on Tuesday, July 10th, 2007 at 8:07 am and is filed under Gear, Flying, Cross-country. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.