Survival After the Forced Landing

Here's a presentation (and lecture notes) I put together and gave at my local airport recently on some ideas for improving your odds of surviving a forced landing. This was largely inspired by preparation of the Alaska trip featured earlier on this blog.
Survival After the Forced Landing

ADS-B receiver & iPad combo: Early Impressions

Now that you've read all about what ADS-B in and FIS-B are, here are some screen-captures and commentary of my early experiences using it. Also: One piece of reference material that may be interesting if you're still learning that I forgot earlier: AIM section 7-1-11.

The setup I'm using is an Apply iPad (first edition), the SkyRadar ADS-B receiver, and either SkyRadar's own iPad app, or the Hilton Software WingX application. Which app to use is probably best left up to you: Both are available for free trial. After that, WingX requires a subscription fee, and the SkyRadar app requires a fee to update charts, but appears to continue to work afterward for free for displaying the ADS-B data.

In subsequent posts I'll get into discussing traffic (through TIS-B), data coverage, and some of the other quirks I've noticed. This post is all about the FIS-B data you can receive and how each app handles it.

The executive summary on which app is better for the FIS-B data is a toss-up: Neither support 100% of the data being transmitted, which is unfortunate. They get the most important bits, with WingX getting the edge for my vote in terms of organization of weather data. Because of these limitations my plan is to use WingX as my primary charting and weather display app, but will keep the SkyRadar app installed in case I need data I might be missing.

Over the past couple of months I've flown several trips with the setup, which is where I got the screen captures below. Most of the time I ended up using WingX, and have subsequently paid for an annual subscription. I'm going to skip describing the core features of each app in favor of concentrating on the FIS-B data. The WingX folks have some pretty good video documentation describing their product which you may want to view before purchasing their app, and the SkyRadar folks PDF documentation you can download.

NEXRAD (weather radar) is downloaded in 'strips'. You can overlay radar on any of the chart types (i.e sectional, en route IFR, topographic, or a blank map where you can add other aviation layers like airspace, airways, etc. My preference was to overlay the radar on an en-route IFR chart. Areas where radar data has not been received (or are outdated) are slightly opaque, giving you a very clear picture of what radar data you have (or are missing).

Local NEXRAD granularity - WingX

En-route NEXRAD - WingX

 A few interesting observations about radar using this setup:

• High resolution "local" NEXRAD images are downloaded for approximately 200-250nm of your present position. The FAA says 250nm in the AIM. In practice I noticed a few opaque 'strips' toward the outer reaches. Based on this I'd say 200nm is a good safe range. This seems fine for the type of flying I do but folks flying faster (i..e turbine) aircraft may have a different impression. Then again, they are more likely to have on-board weather radar 

Local NEXRAD coverage on a clear day - WingX

• How old is that image, anyway? The WingX support folks who told me old data 'strips' were made opaque after 10 minutes. SkyRadar has the data's age printed right there on the screen -- but its not clear what that age means considering you could be looking at many strips of radar data at a time (i.e. if you zoom out a bit)

NEXRAD "strips" that were too old or not received. This usually corrected itself within a couple of minutes. Occurs in either app - WingX

• The AIM says the local NEXRAD data is broadcast on a 2.5-minute interval, with new data arriving into the FIS-B system every 5 minutes. By my math, an image you're looking at as valid on the screen could be 25 minutes old, worst-case (NEXRAD itself takes 5-10 minutes to produce an image). Needless to say, this is not a tool you'd want to use to tactically avoid convective weather or to try to make a run through a 'hole'

• A low resolution NEXRAD composite for the continental U.S. is transmitted on a slower interval (10 minutes). The SkyRadar iPad app displays it, but WingX doesn't just yet (12-March-2012: A new WingX update arrived which supports the long-range NEXRAD composite. I'll try it out next time I take my airplane up).

Low-res nationwide NEXRAD composite. Useful when you're zoomed way out - SkyRadar.

METARs & TAFs are downloaded within either a 100 or 500nm range, per the AIM. In practice I have seen METARs & TAFs consistently available for out to about 500nm away away from my position on every flight.

A nice thing about WingX is how it manages this data. You tap next to an airport (any airport), hit weather, and the METARs/TAFs/PIREPs (etc) are displayed with the closest to the station first and radiating out from there. This is simple and intuitive, and means rapidly getting at the information you want (how's the weather surrounding some point in space) without a lot of head-down time in the cockpit. I like that.

TAFs - WingX

METARs - WingX

With the SkyRadar app, you've got to scroll over each airport of interest to display its METAR and TAF (if they exist at that airport).


PIREPs are downloaded within a 500nm radius. I did a couple of tests to see how efficient the system is at disseminating a pilot report. Flying over the California/Arizona border going east, I gave a pilot report verbally to flight watch. It was mostly benign weather, so I reported a smooth ride and the calculated wind aloft. It never showed up on the ADS-B feed. When I looked for it online after landing, it wasn't found either - I can only assume the flight service guy never sent it in.

My PIREP - WingX

On the return trip a couple days later, I encountered some mountain wave in western New Mexico and gave a pilot report. My PIREP showed up on the ADS-B feed to the iPad about 5 minutes later. Very cool. Similarly, on a recent trip to southern California where I diverted for weather, the receiver picked up pilot reports of icing that were brand new, not present when I checked weather on the ground prior to takeoff not an hour before. That helped my decision making as the minimum IFR altitude in the area was right about where the icing PIREPs were.

Similar to METARs & TAFs above, the pilot reports in WingX are shown in order of distance radiating out from a particular station you're interested in. This is an area where the SkyRadar app is lacking; per their documentation you have to go hunting around for an icon next to an airport or VOR nearby to where a pilot made their report (this is per SkyRadar's literature; I never did see any in flight).

NOTAM (D & FDC), and TFRs are sent out with 100nm. That seems arbitrarily close, particularly for TFRs. Displaying NOTAMs is similar to METARs & TAFs above - scroll over an airport of interest with the SkyRadar app, or be given all of them radiating out from some airport using WingX.

Potential gotchas? WingX does not appear to currently support displaying TFR data, and it doesn't explicitly say if it supports FDC NOTAMs. This area is decidedly one where the SkyRadar app does better, pending further software development.

America's most bogus (Disneyland) TFR - SkyRadar

NOTAM-Ds - WingX

NOTAM "D" & "FDC" for Santa Maria - SkyRadar

AIRMETs are sent out within 500nm.WingX provides the AIRMET text in a similar, geographically oriented format when looking at weather for a particular airport. Surprisingly, I couldn't find any AIRMET data in the SkyRadar app, on a flight when there likely would have been one in the area for low ceilings/IFR.

AIRMETs - WingX

SIGMETs are transmitted within a 500nm radius as well, but neither SkyRadar nor WingX appear to support dissemination of these yet.

Winds & Temperatures aloft are sent within a 1000nm radius (so half of the lower 48, roughly). SkyRadar shows these nicely - just pan around an area and you'll see a table of forecast wind & temperature aloft data from the nearest forecast point. WingX does not currently support winds & temperatures aloft from the ADS-B receiver. It will show you winds from the last time you downloaded weather from the internet.

Winds & Temperature aloft data is shown from the last internet weather download - WingX

Special Use Airspace status is sent out within 500nm. This is another product that the SkyRadar app supports, but WingX does not. I had to hunt around to find a hot restricted area using the SkyRadar app. Frankly, its one area of the ADS-B feed I don't think I'll rely on regardless of software support. I want to hear ATC tell me that a particular restricted area is cold before entering. Whether VFR a pilot elects to fly through a hot MOA is a whole discussion and judgement call in itself, but again my preference is to ask ATC.

Special use airspace status - SkyRadar

Intro to ADS-B weather

I last visited Oshkosh in 2010 where I started taking an interest in ADS-B. If you're new to that acronym, you can read all about it here. The prospect of having to spend money on a new piece of equipment (ADS-B out) didn't excite me much, but that won't be required until 2020 anyway. ADS-B in, on the other hand, I found intriguing, particularly after another flight across the country with periodic calls to flight watch asking for a verbal description of weather ahead. That's because a subset of ADS-B in, FIS-B, allows pilots to receive weather data in the cockpit. This post discusses my experiences with FIS-B using portable electronics to receive and display weather information.

Weather in the cockpit has been available for some time through XM satellite data subscriptions, billed at a monthly fee. FIS-B in is free (more precisely, we're paying for it through FAA funding). You need a receiver and something to display the data on, though. The weather and other data services broadcast through ADS-B are discussed in the AIM (section 4-5-9, new as of 2011). I had previously seen XM weather in action while riding in other pilot friends' airplanes as well as with instructional clients, but decided against it due to the nature of my flying (sporadic long-distance trips - maybe one every couple months - where its really handy). Buying a receiver, and then having the data for free, was much more palatable in my case.

One of the fundamental limitations of ADS-B is that it is a ground-based system. You must be within line of sight of a ground station to receive the data. When I was learning about all of this in the summer of 2010, coverage was somewhat sparse, but transmitters were being installed in various locations throughout the country. Fast forward 18 months and the coverage was pretty good; you can see a map here (click "ADS-B" and then "radio stations"). Because ADS-B was now largely available in the western U.S, I decided it was time to give it a try. Note that large areas of the inter-mountain west are still without these stations.

Recall that 2010 was also the year the iPad was introduced, and its place in the cockpit was quickly taking root. Going to Oshkosh and back that year was the first big trip I'd taken using chart data on my iPad. There at Oshkosh I also came across the SkyRadar booth. Staffing the booth were the engineers who had built a portable ADS-B receiver, and integrated it with an iPad app, to display weather data in the cockpit.

After chatting with the SkyRadar guys a while I asked about what was inside, and was surprised to learn they were using technology I'd worked on professionally outside of aviation for the better part of the past decade. This is more of a source of personal pride than anything; I have not received any compensation from their use of this technology and do not anticipate it benefiting me financially in a material way in the future, but I felt compelled to disclose that.

With the technology coming into alignment, at a reasonable price, I decided a buy a SkyRadar receiver late last year and have now had the opportunity to use it on a couple of cross-country trips. I evaluated both the SkyRadar's own iPad app and WingX -- currently the only two iPad applications I'm aware of that will display data the receiver picks up. In subsequent posts I'll get into my experiences using the receiver on a few trips. Many screen-shots to come.

In the mean time, AvWeb has put together a pretty decent video comparing the SkyRadar ADS-B receiver and the WingX app (what I'm using) versus an XM weather receiver and ForeFllight:

Formation fun

With my Alaska trip written up I've come up with several ideas to keep this blog going. Some will be trip reports, some surrounding technical aspects of flying that have interested me enough to further my education on.

...but sometimes, you just have to go out and have fun. I've flown the San Francisco "Bay tour" many times. One day last year, several folks were visiting and a pilot friend and I decided to take them on a bay tour. Why not make it a flight of two? Here's a little clip one of the passengers took near Sausalito.


The sun had just set. Next time, we need to get up there before sunset to get the #2 airplane basking in that "golden hour" light outside the bridge. That was also the flight where I got the image that's presently at the top of this blog -- the sun was just above the horizon then, just past abeam SFO.

Formation flying is a fun challenge. Like many things in aviation, preparation is the key. We had a lengthy preflight brief going over our plan and several what-if-type scenarios. Flying the #2 airplane, I didn't enjoy much of a bay tour at all - my eyes were glued to the lead, who scanned for traffic, talked with ATC (we were treated as a single airplane), and the like. I'm by no means a formation expert but had some good training on it, along with aerobatic flying, shortly after receiving my private pilot license many years ago.