455 Bravo Uniform
Final Approach
Silly question - when you guys are using these things for charts, weather, and navigation, are you using the cell signal (surely not?)? I'm not understanding how this works.
How would an iPad or iPhone work?
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Shawn
En-Route
In a program like Foreflight or any EFB, all of the charts, AFD's and documents are downloaded ahead of time when you are connected to the internet on the ground locally to the device for use in flight...hence EFB's are typically storage hogs when it comes to available storage on your device.
Navigation uses either the internal GPS on the device or for more reliable and accurate GPS you can connect an external device like a Stratus 2 that is the GPS receiver and ADSB receiver. There are several devices other than the Stratus 2...that one just works best in conjunction with Foreflight program.
A device like the Stratus 2 is an ADSB receiver which will receive weather and traffic info that is broadcast by the ADSB towers...not over the internet...and your device is connected to the external receiver in your plane via a wireless network. No internet connection via cell data or wifi is needed in flight.
Just like you need to make sure you have the correct and current paper sectional for wherever you are flying, with an EFB you need to make sure you have the proper sectionals and charts downloaded and updated prior to your flight.
Navigation uses either the internal GPS on the device or for more reliable and accurate GPS you can connect an external device like a Stratus 2 that is the GPS receiver and ADSB receiver. There are several devices other than the Stratus 2...that one just works best in conjunction with Foreflight program.
A device like the Stratus 2 is an ADSB receiver which will receive weather and traffic info that is broadcast by the ADSB towers...not over the internet...and your device is connected to the external receiver in your plane via a wireless network. No internet connection via cell data or wifi is needed in flight.
Just like you need to make sure you have the correct and current paper sectional for wherever you are flying, with an EFB you need to make sure you have the proper sectionals and charts downloaded and updated prior to your flight.
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simtech
En-Route
The cellular version has WIFI and with that it has a GPS chip. If not cellular version then you will need an external GPS signal. For charts you down load them before a flight on wifi or cell service. Weather is ADS-B so for foreflight you will need a stratus unit or make one.
not silly at all. think of it this way. the tablet functionality is split into groups....charts, GPS and real-time weather. charts, the AFD, plates, etc. are stored on the device and downloaded from the provider into the device either thru a cellular data connection or wifi. the GPS functionality (at lease on the iPad mini) requires the cellular data chip. this chip is an option on the (usually) wifi only iPad. without the chip you'd need an external GPS device attached to your iPad. real-time weather requires (at least on my iPad mini) an external device such as the Stratus which receives data and integrates it into ForeFlight onto my iPad.
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Pilawt
The Stratus receiver sends the ADS-B data from FAA's transmitters, along with GPS data, to your i-Gadget via a Wi-Fi connection. The Stratus box is a Wi-Fi hotspot (no internet connection).
Stratus uses Wi-Fi instead of Bluetooth for the wireless connection in the airplane, so that any number of i-Gadgets can connect to it simultaneously. And when multiple devices are on the same Wi-Fi network, a route entered in Foreflight on one is automatically transferred to the other(s). Bluetooth would allow use of only one device at a time.
Stratus uses Wi-Fi instead of Bluetooth for the wireless connection in the airplane, so that any number of i-Gadgets can connect to it simultaneously. And when multiple devices are on the same Wi-Fi network, a route entered in Foreflight on one is automatically transferred to the other(s). Bluetooth would allow use of only one device at a time.
455 Bravo Uniform
Final Approach
You guys are awesome. Thank you.
I did not realize that the "GPS function" on some i-devices was real satellite based GPS and just thought it worked off of cell towers, so when cell service was lost, "GPS function" was also lost. I thought that's how older iPhones worked. Behind the times. That's why my kids laugh at me.
I did not realize that the "GPS function" on some i-devices was real satellite based GPS and just thought it worked off of cell towers, so when cell service was lost, "GPS function" was also lost. I thought that's how older iPhones worked. Behind the times. That's why my kids laugh at me.
Shawn
En-Route
You are not completely incorrect in your thinking...having internet service increases the accuracy and reliability for the GPS in the devices. Many people fly just using the device's internal GPS, but I have had several time where that signal and accuracy was unreliable in the air which is why I went with an external GPS receiver that I connect to.
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Pilawt
IPhones and cellular-version iPads have good GPS chips in them. Using the internal GPS, Foreflight will generally show an accuracy of 5 to 10 meters. But when importing the GPS signal from the Stratus, it's usually down to 2 or 3 meters. That's pretty good shootin'.
Everskyward
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You also need to make sure you download the background map before you leave cell or wifi coverage. Otherwise, even though the GPS is working it has nothing to project itself on. It's the reason that some non-aviation map programs don't work when there is no cell service.
455 Bravo Uniform
Final Approach
Cool stuff. Not that I could even see the tiny display on my old no-service-plan iPhone 5c, but if I got Foreflight on it, GPS would work?
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It should. IIRC, a Foreflight subscription allows use of one iPad, one backup iPad, and one iPhone. Having the latest iOS on your device lets you use the newer Foreflight versions, which have more features and download updates more quickly.
You can download it and try it for a month free. See their FAQ page.
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Coloradokevin
Pre-takeoff checklist
On the GPS issue, if you are planning to get an iPad, plan on buying one of the cellular capable models (even if you don't plan on having a data plan). Apparently there's a difference in how the iPads are made, and only the cellular version has an internal GPS. If you want to be able to use Foreflight while in-flight without an external GPS (like the Stratus) you'll want the cellular-capable version of the iPad.
I never activated a data plan on my iPad (use it on wifi at home and work), but I do use the GPS function while flying (which hasn't given me any trouble thus far). Again, if you plan on pairing the iPad with a Stratus (or other external GPS) this is a non-issue. But, I wanted the flexibility to fly without those other devices, as I do right now.
OTOH, I am on my third iPad over the course of about 5 or so years. All have been WiFi only with an external GPS feed. I have not found it to be an inconvenience at all.
Different strokes.
All I pads have wifi. What you mean is the GPS is on the cellular radio chip. A wifi-only doesn't have GPS.
And to answer the other question, you will see no problems with the integral GPS use if you do not turn on the cellular data subscription.
TangoWhiskey
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Just to clarify: you actually DO use WiFi when using your iPad with Stratus; that's how the two devices communicate with each other. But you're connecting to a hotspot/network that the Stratus generates, not a ground-based WiFi network.
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Aztec Flyer
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I use a full size iPad and prefer to keep my phone separate from my tablet, so went with the less expensive iPad. I use a $100 Garmin GLO for the GPS signal source for my iPad running Foreflight. The GLO picks up both the US GPS satellites and the Russian Glonass signals, It's tiny compared to a Stratus, doesn't need to be mounted on the glareshield (I leave it in the seatback pocket behind me), the battery lasts longer than the iPad battery inflight.
The Stratus 2 does more, but I haven't quite got myself to the point of springing for the considerable extra cost.
MAKG1
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Foreflight will claim that accuracy, but it's wrong. I've found discrepancies of up to 0.3 nm, compared to other (WAAS) GPSs and terrain features, with Foreflight claiming 10m accuracy, at 1000 AGL. There is clearly some systematic missing from that "accuracy."
Keep in mind the $99.00 GLO and the $550-$900 Stratus are two completely different creatures. The GLO, like the similarly-priced Dual XGPS150 and Bad Elf, are GPS receivers. Stratus and its similarly-priced cousins are ADS-B receivers that include GPS capability and sometimes AHARS as well.
I use a Stratus most of the time but I still use my Dual occasionally. When I do, I don't even toss it it in the back seat pocket. I toss it in my shirt pocket
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Snorting his way across the USA
For VFR nav, the accuracy of the internal GPS is more than adequate, and if it isn't, it will let you know. If IFR, you aren't shooting approaches with the Ipad anyway.
455 Bravo Uniform
Final Approach
Does integral GPS on phone/pad still work if "airplane mode" is selected?
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I didn't think it did, but it seems to.
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Pilawt
As to my iPhone 6 and iPad Mini 4, both running iOS 9, the answer is yes.
and a big cost savings. I am in the same boat as you.
It takes forever to boot up if the phone is in airplane mode, but it works.
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If you're looking to go cheap EFB you could do what I did. Went to Verizon bought an Ellipsis 8 for $50. They upgraded my data plan with the E 8 for the same price I was paying before. Downloaded a free aviation app called Avare and have all the usual charts georeferenced on my display. Bought a cheap universisal kneeboard strap to clamp on to it and works great. Oh yeah, I operate in airplane mode and the internal GPS works fine.
I use a WiFi only iPad, no/no internal GPS - I use an external GPS (Dual); you can use a smartphone as an access point for your WiFi-only iPad ("tether" the iPad to the phone). Your service provider will charge you something for it, or you can root your phone and do it yourself, if you don't mind stepping through all the hoops. I speak only of Android phones - no experience with iPhones.
denverpilot
Tied Down
You taking about Foreflight @flyingron?
I just tested this on iPhone 6+ and cold start time for the App was identical for cell+wifi and airplane mode.
????
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The Cellular version allows you to use the full set of features in ForeFlight such as filing a flight plan. However...If you have a smart phone with you at all times you can probably set it to act as a "hot spot". The Cellular version does also get you a good GPS chip as well. I have, and recommend the Cellular version. You will forget the cost difference in a couple of days.
No, I'm talking about the GPS position initializing (separate from any application).
denverpilot
Tied Down
Haven't seen that either so I just tested it.
Blue dot came up instantly on the house location in FF with Airplane mode engaged. (Also played with other GPS non-Aviation apps and they all came up fine also. I suspect that's because they're all using iOS Location Services under the hood anyway, none have direct access to the GPS or Cellular Assisted GPS data in the chipset.)
Now I'm curious about the circumstances needed to see what you're seeing.
Put the phone somewhere that it can't see the GPS satellites or completely power it down.
The common situation is when I've powered my phone off when flying on the airlines. When I get to my destination if I power it up immediately into airplane mode it doesn't get the position info for a long time. If not in airplane mode, it comes up immediately.
The common situation is when I've powered my phone off when flying on the airlines. When I get to my destination if I power it up immediately into airplane mode it doesn't get the position info for a long time. If not in airplane mode, it comes up immediately.
Farmboy
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One thing I'll pass along is I that I find foreflight on my iPad mini excellent. After using it for some time I went and downloaded foreflight on my iPhone 5, and i can't stand trying to use it on the phone. It's laid out differently, and obviously smaller, but the differences show me that unless it's a quick check of the weather, the phone version has no value to me. (Which is quite contrary to the value I place on the iPad version).
FastEddieB
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Ditto with WingX7Pro in my iPhone 6+. Great on my iPad Mini, marginal on the iPhone. I've asked Hilton software if they could make the iPhone version for the 6+ emulate the iPad interface, to no avail.
denverpilot
Tied Down
Isn't that explainable by normal "GPS Cold Start" behavior of any GPS receiver?
Usually the phone would get an "assist" on knowing it's general location and network synched time source to be able to know what satellites to use, from the cellular sub-system, but inside a wimpy aluminum faraday cage in an unknown location, weak cell signal etc... most GPS only receivers will take a while to find which satellites are overhead and figure out a three satellite solution that makes sense.
I suspect inside Apple's "Location Service" there's a way to ask it for only a >X accuracy level from the app itself, too... so until that subsystem has decided the GPS is all it's going to get and it is happy with the reported accuracy, it probably doesn't get anything, but I haven't coded anything to talk to that API/library. Someone here has if I recall, from an old thread. Maybe they'll pop in and say how the location subsystem behaves when you ask it for things it doesn't know ... yet.
I will say that the reliever capabilities in some of the cheap GPS chipsets is utterly astounding these days, with them seeing far more satellites than older models when in the same location with their original stock antennas. The filter magicians really seem to have made their sensitivity amazing without affecting their selectivity that much which is a traditional trade off in RF receivers. I sense much black magic going on there.
Whether the receiver or antenna setup inside a phone is ideal, is probably a foregone conclusion that it's not, too. It'd be fun to get an iPhone into that "I'm lost and don't have a cell signal either" state and compare it to say, an old Garmin GPS-III handheld or something ancient that doesn't hear well and see if they take similar amounts of time to find the closet and resolve a location.
If I had to place a guess as a hypothetical QA software person, I'd also put $5 on the Location Services code blocking on the network time code object and even though I'm pretty sure internally iOS is using UNIX time, the phone going into "I'm scanning for a cell network" mode, probably hard blocks the object call that the GPS chipset needs to get the current time hack so it can reference the internal cache of what GPS satellites should be "in view".
It shouldn't, I mean I would think they could put an RTC cheap chip in there to hold time when the phone is "powered off" (...amazing how the power button still works eh? Grin...) and read that, and if they do this portion doesn't hold water, but I've seen dumber designs on more expensive products that assumed things would be available that weren't.
All interactions that would slow things down in your scenario. Just guesses. Would have to crack open the developer tools and play to find out. And probably make a little faraday cage to put on the desk to shove the phone into. Heh.
Not to mention flat out bugs. My buddy at work today and I marveled that his iPhone has been exactly one minute off of the cell network for days since he returned from Florida. On a whim I told him to turn network time synch off, exit that menu, reenter the menu and then it back off, and exit again. (Recent iOS seems to hold changes for a while if you linger in a settings menu, but if you exit the page it does it right away, something else I noticed just watching the behavior of forcing cellular network changes manually.)
He did it and within a second or two his phone jumped forward that lost minute. Cute bug.
That's the whole point! The GPS check uses the cell radio to help with the cold start. You disable it, the cold start takes longer which is EXACTLY what I said in my initial post.
denverpilot
Tied Down
Not really. You said "it" (Foreflight) "takes forever to boot up if the phone is in Airplane mode". See above.
There was absolutely nothing about being inside an aircraft tube, changing timezones, or the phone being all the way off for an extended period of time, until later.
And even without a GPS location, Foreflight itself takes no additional time to 'boot up' that I can reproduce. It just doesn't have any location dot or aircraft symbol on the maps. It's fully "booted" and working but not going to provide any location based features until iOS says to it, essentially, "location information is good".
So what are you saying takes longer? Are you saying that Foreflight "booting up" includes the location indicator appearing? That's what I'm trying to figure out. I can't reproduce a slow startup of Foreflight itself just by turning on Airplane mode.
Stewartb
Final Approach
FWIW, I maintain current charts and the A/FD for Alaska, a worldwide map, USA airport info, business directory, high res terrain for north america, terminal procedures, obstacles database, etc on my iPad and it consumes 5.6 gigs. My iPad is a 128g model so I find the storage requirement for Foreflight to be reasonable. In fact I maintain the same Foreflight downloads on my iPhone, too. And I use Garmin Pilot as my primary app so I have most of the same stuff downloaded for that on both devices (1.4 gig but no A/FD and only about half of Alaska sectionals). Foreflight documents like the terminal procedures and A/FD only load on the iPad app and not on iPhone, by the way. In any case no storage problems for me.
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No "it" meant the GPS chip in the phone. The whole thread up to that point had been about the merits of external GPS units and the internal GPS/Cell chip. Foreflight was only tangetially involved. I'm sorry you misunderstood me, but that does not make what I said wrong.
denverpilot
Tied Down
Fair enough. Lamenting normal GPS startup seems like a weird thing to do, though... every GPS that doesn't have an onboard clock on the planet does that. For decades...
Thus... why I thought you were talking about Foreflight and tested it.