Thursday, May 12, 2016

HobbyKing Aether 3.7 Review Part 1

HobbyKing Aether 3.7 
Aether V2 2016

This blog contains my experiences with the Aether 3.7 I received from HobbyKing for review.

The HobbyKing Aether 3.7 is the second version of the popular Aether 3700b electric that came out in 2015. This time around HobbyKing has made modifications to the plane and is actively marketing it as an entry-level ALES glider.

Note on Aether Versions:
  • In this blog when I use V1 I'm referring to the Aether 3700b released in 2015
  • In this blog when I use V2 I'm referring to the Aether 3.7 released in April 2016
RCGroups has two active threads for the Aether:
  1. Aether V1 thread (this thread describes the aircraft released in 2015)
  2. Aether V2 thread (this thread describes the aircraft released in 2016 and the plane that we are describing here)
These are the aircraft specifications as listed in the HobbyKing Aether web page:

Features:• Almost Ready to Fly - Complete final assembly, install electronics, and fly!
• Built up balsa wing and tail surfaces covered light weight iron on film
• Sheeted D-tube leading edge
• Fiberglass fuselage pod, with woven carbon fiber boom.
• 4 piece wing for easy transport
• Affordable entry level ALES model
• Bolt on tail surfaces
• Complete hardware pack
• Airfoil AG24
Wingspan: 3700mm
Length: 1861mm
Flying Weight: 2300g w/o battery

5 Channel Transmitter and Receiver
4~5S 14.8~18.5V 3300~5000mAh Lipoly Battery
60~80A Brushless ESC
6 x 22g Servos
35 size Brushless motor
50mm Spinner and Folding Prop

Lets start by saying that HobbyKing caused a bit of a stir in 2015 with an under $300.00 3.7-meter glider. The Aether 3700b thread has been one of the most popular threads in the "Electric Competition Soaring-F5J/ALES/e-Soaring" section in RCGroups.

Multiple comments were made about this aircraft. Comments about how it could finally be an inexpensive Pulsar came around and rebuttals indicating it was impossible to sell such a glider at that price. In the end the, Aether 3700b got a bit of exposure and tons of mods and recommendations were posted online on how to make it better.

HobbyKing offered to have a follow up version that took into account many of the comments of our online community. The result is the Aether 3.7. We've started a new Aether 3.7 thread in RCGroups to cover this plane.

Big Bird

Before you order this plane keep in mind that this is a big model. You may have to go outside your house to assemble the whole thing.
I have provided measurements in the photos in the hope that it will help you.

Remember that transporting this size plane
to the field may be a challenge. Fortunately the the wing can be built in 4-parts.

In addition to bench space you are going to need some kind of stand to hold the plane confortable while you install parts and adjust the moving surfaces. In my case i used a slightly modified saw stand.

I don't have the most organized shop and at times it was a challenge to have enough space to put this bird together.


Opening an ARF of is always a source of stress for me: what if something is damaged, what if there are missing parts, what if it is the wrong color. The basic rule is to inspect the box before accepting it from the shipper. If the box is significantly damaged refuse delivery. However we all know that damage may not be apparent until we unpack all parts. 

In both V1and V2, I was very happy to see most pieces individually packed and protected. I had zero damage and no missing parts. This is very welcome as several people reported missing parts on V1.

Had to use a knife to carefully cut though several layers of tape and wrapped plastic bags to get to the parts.

Do not wait until you are ready to build this plane to inspect if all the parts are in the box. The sooner you find out what is missing the sooner you will receive replacements for missing or damaged parts.

Upon opening the box you will find the nice glossy manual. This is a much welcome improvement over the CD-ROM that was included on V1.

Unfortunately the manual is missing a compressive list of parts. I strongly recommend that you read the manual cover to cover and make sure that all the parts mentioned and photographed there are present in the kit.

You may have to re-bag some parts as the only way to get to them is sometimes to cut through several layers of tape and folded plastic bags.

A very welcome addition is the laser cut plywood to build a jig to properly align the pod and boom.

Another welcome addition is the rod glued on the canopy. Be very careful removing the canopy. You need to lifted a little on the back and slide it to the back until the rod in the front comes out of the hole.

The hole on the front is cut on a very thin piece of plastic it will crack very easily.
Note that the plywood equipment cradle has now been removed.

Responding to the voices in the V1 thread hobby king gave us a fiberglass firewall. It is a big improvement over the plywood firewall on V1.
The firewall comes pre-drilled for the recommended motor.

I am sure some folks would have preferred an aluminum firewall though.

A modification that didn't make the cut this time around was a redesigned wing attachment. This is sad as many modelers will find the current arrangement insufficient and will spend time modifying this. There are plenty of suggestions in the V1 thread.

The long CB rod is not part of the fuselage, is the wing joiner and it weighs 44g.

The carbon fiber boom weights 145g.
The Pod with the canopy attached si 287g.

Be aware that the pod is molded from very thin fiberglass. Precision landings cannot be done like a spear. Be careful or you will crack it easily.
Except for a minor redesign of the servo bay the Fin/Rudder assembly remains the same.
Still in place are the CA hinges and the huge 45º bevels. Some may consider using some kind of seal gaps.

Experience has taught us not to rush to glue the CA hinges until later.

Total weight of the Vertical Stab and Rudder weigh 36g. Be mindful that a servo will be installed here. This servo has a big impact on tail weight.

The Horizontal stab and elevator are the same as V1. Again the gap is significant and some modelers will chose to fill the gaps.
Also keep in mind that the screws that hold the stab in place go through balsa without a hardwood reinforcement. Some may want to consider putting small carbon fiber tubes there.

The Horizontal stab and elevator weigh a total of 64g

The flap wing sections. The flaps have been redesigned they now move down to 90º.

It does not include any pre installed hinge mechanism. The manual instructs you to use "clear tape" to secure the flap.

You must be careful with this. If you tape the flaps wrong it will not move properly. If the modeler has never used hinge tape it be worthwhile to spend a few minutes watching a few videos on the matter or reading about it online. It is not difficult but it can be tricky.

The wing mount screws are predrilled. But as in the case of the elevator they go right trough the balsa with little reinforcement. There are plenty of suggestions on V1 on what to do about these holes. Small carbon fiber tubes seem to be a popular suggestion.

The screws here are no longer metal but nylon screws.

In my opinion the airfoil has not changed.

Center panels weight 282g and 281g

The Aether wing tips are the same as Version 1.
The stoping hole on the rear does not lead to an internal carbon fiber tube as in the middle and aileron sections. This will prove a difficulty when assembling the wings. Little carbon fiber rods are used to align the tip sections and it is very easy of the tube to fall inside the tip section.

The aileron sections look the same as V1. I would have preferred to see hinges made in the same way as the flap. But they kept the CA hinges and the 45º bevels. Again opportunity to seal the gaps.
You must resist the temptation to go ahead and glue the CA hinges. Please wait until the whole wing has been assembled. It is very easy to end up with the ailerons rubbing against the flaps or the tip sections.

Depending on your transportation and storage space, you can have a 4 section wing. I chose to make this one a 2-section wing.

The aileron sections weighs 170g and 169g

There is a number of assorted small parts. You must go through the manual and make sure you have them all. This can be frustrating since there is no central list of parts.

The vertical stab cradle is not a flat piece of wood anymore.

The horizontal stab cradle is the same as V1. No fairing modification was found in V2.
The servo is mounted here. I had to modify the servo tray slightly to allow my servos to sit correctly and securely.

There is an apparent lack of logic in the packing of the hardware. I had to open all bags and match the parts against the manual to know exactly what they all were and to ensure nothing was missing.

Unlike V1, this plane includes a full manual. I urge you to read it front to cover before assembling anything. I believe the assembly order can be improved to avoid problems.
I found the lack of a comprehensive part list annoying.
Also this is not a step by step manual it assumes a certain level of expertise on the part of the modeler. This is not for the novice.

Go to Part 2


  1. modèle intéressant
    quelques petits défauts mais vu son prix...

  2. gros problème avec les clés d'aile externes ! dièdre trop élevé : solution les refaire ! 4 épaisseurs d'époxy 1.5mm ! on ne peut pas modifier le dièdre des clé*s droites dans l'aile ! tailler, recoller ! le fuselage présente des faiblesses ! il faudra renforcer avec du tissus ! travail de montage assez conséquent !
    toutes les chapes ne valent rien !

  3. I really like the work that you do here frend and happen to think that your reviews are really great, sincere and honest. Keep up the good work. You are awesome.

  4. It is good that you have shared this story with us. ALS sickness needs to be addressed and people should be aware. I hope everything is okay for you