Vladimir wrote:
That’s what I meant. No app will have a 50GB database, but on the other hand they don’t need as detailed information as X-Plane.
Exactly. Here’s the blurb from the ForeFlight site about the sizes of their downloads (NB this is North America only). For the avoidance of doubt, I have no affiliation whatsoever with this company, I just use their product.
How much disk space will ForeFlight Mobile take up on my device?
The ForeFlight Mobile app alone (with no data downloaded) uses about 350 MB of space once installed on your device. The app plus minimum required downloads (Airport Database, Business Directory, North American Obstacles, Terrain Map, and World Map) but no charts or plates requires 1.5 GB of space.
For use in flight, ForeFlight Mobile can store airport diagrams, terminal procedures, and navigation charts for the United States and Canada. More storage space will be consumed once you start downloading charts, maps, documents, and more. The Downloads page (More button > Downloads) lists the approximate size of each download so you can estimate how much space is required for your selections.
Download sizes can vary greatly, depending upon your selections. If you want to download everything available, plan on the USA lower 48 States and Hawaii taking about 15.5 GB and Alaska taking up about 4.5 GB of storage space. Canada will require about 11 GB for all available downloads. Downloads for the Caribbean, Mexico, and Central America take up about 1.9 GB.
If you do not plan on downloading all of the USA or Canada, a good rule of thumb for the USA is that each state requires, on average, 320 MB to download all items (i.e.: Terminal Procedures, IFR and VFR charts, WAC charts, High Resolution Terrain, etc). Larger states like Texas or California will require more space. Alaska alone takes up around 4.5 GB of space. Canada requires, on average, 850 MB per Province or Territory with all available items selected. Larger areas like Nunavut will take up about 3GB of space.
A few items displayed on the Downloads page display a compressed file size. This means the actual size, when de-compressed (un-zipped), will be larger when the file is installed. The compressed items are as follows:
– United States (lower 48) high resolution terrain is a 242 MB download and takes up 1 GB on disk.
– Mexico/Caribbean/Central America high resolution terrain is a 96 MB download and takes up 737MB on disk.
– Canada high resolution terrain is a 334 MB download and takes up 1.4 GB on disk.
– Alaska high resolution terrain is a 56 MB download and takes up 947 MB on disk.
– Worldwide low-resolution terrain map is a 61 MB download and takes up 320 MB on disk.
- Airport Database is a 133 MB download and takes up 670 MB on disk.
People mention frequently “consumer product” in this conversation. You would be surprised by an inside look into the development of certified software. The main difference is the sheer amount of paper to protect those who carry responsibility and the underdeveloped engineering practices of those doing the actual work. I would rather trust well developed uncertified software than the certified one with tons of paper. Consumer products are “tested” by millions of people while the other depends entirely on what has been foreseen and specified.
Backups and flexibility is better than certified and reliable.
Peter wrote:
One can’t be quite as absolute as that otherwise GPS approaches would not be possible.
GPS approaches are possible because they are done with monitored equipment which will flash some kind of warning at you when it senses that position accuracy might be compromised. None of the handheld devices I have used so far (including Jeppesen Flight Deck IFR and VFR) has this capability. The Jeppesen app will show a little symbol in the top left corner of the screen (easily overlooked) when GPS reception is insufficient and remove the “ownship” symbol from the chart. But no real warning or anything.
Runway20,
I don’t really want to continue this conversation on this thread as it’s really off topic, and I don’t want to be disrespectful of our colleague who we’ve lost.
But I can’t help but wonder if your database has been corrupted? Have you contacted SD about it? Using the same altitude, in EasyVFR that whole area is red!
You can see in your own screen shot a peak of 4091 in the top left with no colouring, but your aircraft altitude appears to be 2540ft.
Perhaps better move these posts to the SV thread.
I’m not sure about SV.
EasyVFR has both SV (called 3D mode) and Relative Terrain Shading (ground turning yellow or red as you get too close). If I’m ever concerned about terrain, it’s the later that I use. I’ve never used SV other than for testing.
The problem with SV is that it doesn’t show you the way out of the terrain. Sure you can avoid hitting the thing right in front of you, but for how long do you make turns before you end up in a dead end valley? With Relative Terrain Shading, you can see which exists lead to a way out.
Agree with @Stephan_Schwab – “certified” versus “non-certified” does not correlate with the quality of the underlying software, or its data sources.
And it’s silly to drop all “consumer” stuff in the same bucket.
For example I would consider Garmin Pilot with a Garmin GDL 39 (WAAS) receiver to be far closer to certified avionics quality than SkyDemon running on a generic Android device and internal GPS.
In fact in a “terrain avoiding emergency” I would rather rely on Garmin Pilot (with its 90 day terrain database updates and WAAS GPS source), than the terrain feature in a Bendix King panel mount with 15 year old data and 15 year old software engineering.
And I’m really bored of this “iPads shut down all the time” nonsense. Carry a spare. Don’t smother them in a case. Don’t charge them if warm. And if it’s an IMC emergency they won’t be in the sun either.
Get a newer iPad already. I used my Mini 4 in South Africa in 25C OAT continuous and the tropical sun pounding on the cockpit for hours, it did not quit or lose GPS long term. Even if there are gaps here and there, it does not just plain die, and the vertical cut is incredibly valuable. In general it runs much cooler than my old iPad 3.
I kept my iPhone out of the sun (except for the occasional picture) as spare with the same track preloaded.
BTW That is why I don’t split my SD account with someone else like is fairly usual, I want to have the 2 portable devices for myself, one main one spare. And a big portable battery pack and cables at the ready.
If you zoom out the MFD image, like in the picture I posted, you can easily see the valleys or lower terrain and take that direction (the airplane icon is in the center). Of course if you are at a few hundred feet above terrain it might not help you much.
Data in the G1000 comes from Jeppesen. You can update TAWS, Terrain and Obstacles (paying).
From my experience, so far what I see on the screens always matches what I see outside.
But again, it is not a navigation instrument, it’s just an enhancement for situational awareness, even though it’s pretty accurate all the way to touch down. During an approach, if you aim the runway threshold, it will bring you there with the lateral accuracy of a non precision approach with wind corrections to reach it..
I agree, the newer iPads don’t heat as much as the older ones. My iPad never shuts down in the DA40 Cockpit which can get hot in summer. On the other hand, SD can freeze. It happened to me a few times and had to reboot it to recover a functional app.
So I would’nt rely completely as that for sole backup/emergency device.
