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Mar 25, 2020, 11:07 AM
Better SAFE than sorry!
Thread OP

Spektrum AR637/630/631/8360 and Using SAFE

Following in the footsteps of the Eflite SAFE RX in another plane thread, this thread will be all about implementing SAFE in different airplanes using the Spektrum AR637T receiver and similar receivers that use the same setup process in Forward Programming. That "SAFE RX in Another Plane" thread is all about implementing SAFE with an AR636 or the Apprentice S receivers.

The AR637TA is included in some Bind-and-Fly (BNF) models from Horizon Hobby with SAFE features, but the AR637T is the first open-stock Spektrum receiver that fully supports customizing the SAFE features on your own for any airplane. The TA can be unlocked now through a firmware upgrade so that you can customize settings in those as well.

More general information about the AR637T can be found in this thread.

EDIT December 2020 - Spektrum has come out with several receivers with this capability; added them to the title.
AR637T and TA
AR10360T (seems to be coming soon!)
Last edited by flightengr; Dec 25, 2020 at 05:19 PM.
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Mar 25, 2020, 01:04 PM
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eihoward's Avatar
Let the exploring begin...

The official manual

Receiver setup video Playlist
Last edited by eihoward; Apr 04, 2020 at 03:14 PM. Reason: Added setup video playlist.
Mar 25, 2020, 01:51 PM
Registered User
Mine’s been shipped. Now I’m wondering what plane to put it in when I get it.
Mar 26, 2020, 05:11 AM
Blue Skies
hifinsword's Avatar

AR637T and AR637TA

HERE is a LINK to a POST by Miguel Alvarez, a Spektrum Dev. Team employee knowledgeable in the minutia of the different models of the AR637x series. As of Feb 2020, the AR637TA is the stock Rx installed in the recently released 1.5M Mustang EFL01250 and 1.5M Air Tractor EFL16450 BNF models. They come with the AR637TA Rx. The AR637T is programmable. It seems the AR637TA model does not have a barometer whereas the AR637T model does. The "A" model is also apparently locked with regard to programming of certain parameters with the stock installed software. I guess we'll find out more as they start to be used.
Last edited by hifinsword; Mar 26, 2020 at 05:38 AM.
Mar 26, 2020, 05:29 AM
Blue Skies
hifinsword's Avatar
There's also some good info on the AR637T in THIS THREAD, "New SRXL2 Spektrum Receivers coming - AR6610T, AR637T, SPM9747". It also covers the SPM9747 serial remote SPM9747 Rx, which may be used with the AR637T.
Last edited by hifinsword; Mar 26, 2020 at 05:41 AM.
Mar 26, 2020, 07:25 AM
AndyKunz's Avatar
The "lock" is temporary, as he explained, and will go away once we have the updated code available for you to download.

Also, OEM mode vs. Open Stock mode. Same code, different mode. The OEM mode is what your BNF models come in, so they can work just like an AR636 does now - wing type, etc. in the rx and a default config in the tx.

Mar 26, 2020, 07:25 AM
AndyKunz's Avatar
Last edited by AndyKunz; Mar 26, 2020 at 07:26 AM. Reason: Network error duplicated post.
Mar 26, 2020, 08:04 AM
Registered User
eihoward's Avatar
any thoughts if the receiver can be used with gas engines...
Mar 26, 2020, 09:30 AM
big12fan's Avatar
Andy, thank you and your team so much for these receivers, I have installed many Eflite Apprentice, 636 and A/B receivers into most of my planes to help teach my son how to fly. It has made transition to other planes easier and cost effective. AS3X has been rock solid and even makes planes more fun to fly for me as well. Look forward to what 637's have to offer. Here's to the next 1000 pages
Mar 26, 2020, 09:36 PM
Better SAFE than sorry!
Thread OP
I've taken a very quick spin through the AR637T menus.

It looks like a lot of the available settings are just like those we're used to from the AR636 with the combination of Spektrum Programmer software (SPS) and my SAFE Model Builder (SMB) program. Each receiver flight mode can be set up as either SAFE Self-Level + Bank Angle Limits, just Bank Angle Limits, or neither. Additionally, you can choose to turn AS3X on or off, Panic Mode on or off, and the two ends of the Throttle-to-elevator (THR>ELE) mix can each be on or off. Other screens let you adjust the bank angle limits for flight modes, the channel and bank angle limits for Panic, and the settings for the THR>ELE mix.

The big difference between the AR637T and the AR636 is that before doing anything with the SAFE or AS3X setup, you must set up the transmitter model for flying the plane as if it did not have any SAFE or AS3X stabilization. That's right - the TRANSMITTER - not the AR637T receiver - gets set up for the correct wing type/tail type, correct control surface movements (normal or reverse), and also the control channels/switch assignments you plan to use for the flight mode switch, panic switch, and gain adjustment input BEFORE you start going through the screens to configure the receiver. If you were to come back later and adjust some of those settings in the transmitter model, you'd have to restart the receiver setup process.

Although this is very different from the AR636, it's probably a lot more intuitive than trying to adjust all of those things on a computer screen. I'm sure the transmitter is somehow sharing all this information with the receiver so that SAFE can still fly the plane correctly on its own. There's definitely a much tighter relationship now between the transmitter and the receiver.

An interesting feature is that the receiver setup can step you through some things to help it detect its own mounting orientation and attitude trim (adjustment for level). If you use the auto-detection for attitude trim with a tail-dragger, be sure to prop up the tail so that the plane is in a level flying position before letting the receiver set the attitude trim.

I see some very interesting things ahead!

Right now, you can plug the receiver in to SPS version 1.4, but the only screen you will have access to is the Software Update screen, allowing you to see the serial number, register it, and check for a firmware update.

The markings on the receiver are very tiny for which way you plug servo plugs in! The signal wire goes up toward the AR637T label and the - wire goes toward the bottom of the receiver (flat side), consistent with the AR636 and probably many other Spektrum receivers.
Last edited by flightengr; Mar 26, 2020 at 09:51 PM.
Mar 27, 2020, 03:59 AM
Registered User
Dave#13's Avatar
I was having a quick look at the manual for the AR637.

I see that HH has coined a new word.

Check the last word on page 8 of the English instructions!

It's a great feature as often my planes need a little help under that condition!

Mar 27, 2020, 08:08 AM
Registered User
That’s because after flying in turbulence you might need some Tums.
Mar 27, 2020, 08:19 AM
Better SAFE than sorry!
Thread OP
Maybe turnbulence is how I tip stalled a plane making a turn that was too tight without enough airspeed!
Mar 27, 2020, 08:47 AM
AndyKunz's Avatar
If that's the only (non-)issue you guys can find, I'd say the author deserves kudos!

Especially if you are exercising the menu options while reviewing the document.

Mar 27, 2020, 09:25 AM
Better SAFE than sorry!
Thread OP
Yes, the manual for this receiver has a lot more info in it than other receivers!

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