Sentry Mini or Bad Elf?

Discussion in 'Avionics and Upgrades' started by Pierce Warren, Jan 31, 2021.

  1. Pierce Warren

    Pierce Warren Filing Flight Plan

    Joined:
    Jan 1, 2021
    Messages:
    20

    Display name:
    Pierce-Tulsa
    I recently just completed my Flight Review after not flying for 6 years. I'm so happy to be back in the skies and loving all of the new technology out there. Especially Foreflight. My set up right now consists of:

    Iphone Xs on a RAM suction cup mount on the left side of the dash (C172).

    I want to be able to have accurate GPS for when I start getting more into Cross Country flights. Basically, I don't want to rely on my iPhone GPS. I want to go into airplane mode and still have GPS. I may upgrade to an iPad soon but just want to get a feel for what I want in the cockpit. I see the sentry mini has WAAS and the Bad Elf says WAAS compatible.

    What is your take on Sentry Mini versus the Bad Elf versions?
     
  2. MBDiagMan

    MBDiagMan En-Route

    Joined:
    May 8, 2011
    Messages:
    4,966
    Location:
    NorthEast Texas

    Display name:
    Doc
    Unless you are looking for ADS-B IN in the bargain, simply buy an IPad with the GPS receiver built in. I’ve been using one for ten years with Foreflight and it has been flawless. If you want to add ADS-B IN to the mix, a Stratux is very inexpensive and does everything that the other receivers such as the Stratus do.
     
  3. Cap'n Jack

    Cap'n Jack Final Approach

    Joined:
    Jun 25, 2006
    Messages:
    8,694
    Location:
    Nebraska

    Display name:
    Cap'n Jack
    I use a Bad Elf, but I have an iPad with no GPS, and I use the Bad Elf for other things, too. I fly C-172, also, and place the GPS on the glare shield. The iPhone should be able to get a good signal in the place you plan to put it. What are your reasons for not wanting to rely on the phone GPS? If I wasn't using the Bad Elf for other things, I'd get the Sentry for traffic and weather, and it also has GPS in. I use a Stratux for ADSB into ForeFlight.
     
  4. GeorgeC

    GeorgeC Administrator Management Council Member

    Joined:
    Dec 5, 2010
    Messages:
    4,568

    Display name:
    GeorgeC
    I have a gdl39 for ads-b in, but I've never had a problem with my iDevices' gps over the past decade. Also, gps works just fine in airplane mode.
     
  5. GRG55

    GRG55 Final Approach Gone West

    Joined:
    Dec 29, 2015
    Messages:
    9,306

    Display name:
    Aztec Flyer
    The GPS in your iPhone is plenty accurate enough for VFR flying. You don't need WAAS.
    I use the GPS in my Foreflight iPad as backup for my in-panel Garmin navigator when flying IFR. Plenty good enough to get me out of trouble.

    If you have an iPad without a GPS the Bad Elf or Garmin GLO receivers work fine as position sources for Foreflight.
     
    MBDiagMan likes this.
  6. Ryan F.

    Ryan F. Cleared for Takeoff

    Joined:
    Dec 23, 2016
    Messages:
    1,271

    Display name:
    Ryan Ferguson 1974
    All things being equal I'd agree with the suggestion to purchase an LTE-capable iPad. This will provide you with an EFB capable of receiving GPS via its own internal receiver (one need not activate the cellular service to enjoy this benefit.) Other than preserving internal battery life, an external receiver such as the Bad Elf tends not to provide any extra advantage. It tends to work just fine this way in the typical light piston airplane. I have done so personally for close to a decade now.

    An ADS-B In receiver may be more beneficial to you as it will provide traffic and weather information as well as a GPS input. If that is of interest of you, go for it.
     
    MBDiagMan likes this.
  7. Daleandee

    Daleandee Final Approach

    Joined:
    Mar 4, 2020
    Messages:
    5,060

    Display name:
    Dale Andee
    Yep ... I have and EchoUAT unit now for ADSB in & out. Before that I used a Stratux unit that I built from a kit that uses a Raspberry Pi.

    https://www.amazon.com/raspberry-pi-ads-b/s?k=raspberry+pi+ads-b

    Add Avare on an iPad and go to it.
     
  8. asicer

    asicer Final Approach

    Joined:
    Jan 1, 2015
    Messages:
    8,819

    Display name:
    asicer
    You know that's not possible, right?
     
  9. Daleandee

    Daleandee Final Approach

    Joined:
    Mar 4, 2020
    Messages:
    5,060

    Display name:
    Dale Andee
    No I did not ... but I do now! I should have used the word "tablet".
     
  10. Dana

    Dana En-Route

    Joined:
    Oct 19, 2016
    Messages:
    3,513
    Location:
    CT & NY

    Display name:
    Dana
    Airplane mode doesn't disable the GPS, but it DOES disable bluetooth connectivity to the external GPS.

    I don't think any of the bluetooth GPS's are any more accurate than the built in one, unless you have a reception problem where the ipad or other device is located in the cockpit. I had one plane where that was the case, so I found a used Globalsat BT-359 Bluetooth GPS on ebay (a cheapo rebranded with some phone carrier's name), it worked fine with an Android tablet and Avare. Next plane I owned, I got a perfectly good signal with the tablet's internal gps.
     
  11. WDD

    WDD En-Route

    Joined:
    Oct 16, 2019
    Messages:
    4,714
    Location:
    Atlanta / KRYY

    Display name:
    Vintage Snazzy (so my adult children say)
    I usually just link my I phone or tablet to the plane’s transponder if it is adsb in and out (Garmin 345, stratus, etc). You get the transponder’s Wass GPS map, traffic, weather, etc.

    If the planes you rent don’t have adsb in /out transponders, then yes buy a Sentry which gives you Wass GPS traffic, weather, etc.
     
  12. pigpenracing

    pigpenracing En-Route

    Joined:
    Feb 8, 2012
    Messages:
    2,757
    Location:
    Brenham Tx

    Display name:
    pigpen
    I have never lost GPS signal with my phone or ipad with the built in GPS.
    My buddy was being cheap and dumb and bought the WIFI only ipad and a bad Elf.
    He always lost GPS signal....
     
  13. WDD

    WDD En-Route

    Joined:
    Oct 16, 2019
    Messages:
    4,714
    Location:
    Atlanta / KRYY

    Display name:
    Vintage Snazzy (so my adult children say)
    Remember it’s not just the moving map but the traffic and weather that’s the big pay off. For that you need a transponder or Sentry type product.
     
  14. Cap'n Jack

    Cap'n Jack Final Approach

    Joined:
    Jun 25, 2006
    Messages:
    8,694
    Location:
    Nebraska

    Display name:
    Cap'n Jack
    Heh. On commercial jets, it works the other way for me. I can use the lanyard for the Bad Elf to keep it in a place with a good view of the sky, while my phones lose the GPS signal if I set them on the table so I don't have to hold them all the time. It's helpful because I often see interesting things and take pictures of them. Because I synchronize the camera and GPS clocks, it is easy to place the image on the GPS track in Adobe Lightroom and get more information about what I was looking at. The exception, so far, has been the 787 because of the electric window shades, but nothing gets a signal when those are turned on. Thus far, I've had no issues in the C-152/C-172.

    I like the moving map more, but I once got to fly to an airshow in MO a few years back with help from seeing the weather. There was a rain storm between KLNK and K57 (Lincoln, NE and Tarkio, MO) but I could see that it was localized and I could fly around it. I picked up flight following and I was told a Bonanza 20 miles in front of my was IFR to K57 and turned around due to the storm and was asked my intentions. I asked for "present course until due west of Tarkio, then fly east". I got to enjoy a nice airshow because I could vector myself around that storm. Another time, I just did pattern work until I saw the storms were on the move towards me and then I landed. I saw where the storms were, and decided not go far so the storms couldn't cause problems for me.