Aspire EP Flying

Update: I am now using the new Sanyo CP1300SCR cells with fantastic results!

Double check your CG and use the recommended control throws for your low rates on the first flight. Switch to high rates if the plane is sluggish. I now fly with maximum rudder and probably 25% more elevator than the 3/8" suggested in the manual.

Launching the Aspire EP with Speed 600 power system is a breeze. Just crank her up to full power and give it a gentle push into the wind at a slight upward angle. The Aspire will be able to sustain a 20-degree climb angle as it climbs out. My plane does not have sufficient right-thrust under full power and has a tendency to circle to the left. This is not a problem at all and can be useful for a circling ascent. My Aspire also has a tendency to climb under power.

I can get 2.5 climbs to probably 500 feet. I am new at this so I really can't judge the height. Total run time is probably 2 minutes and 15 seconds. All I can say is that it is up there a ways and will give me 3-5 minutes in dead air before I have to climb again. I usually do two climbs to altitude and then on the third climb let the ESC cut me off. Total dead-air duration with the nine KR600AE cells is 11-12 minutes.

This setup is only 7-oz heavier than Jerry Festa's Aspire Sailplane in his review in R/C Report Magazine. Yep, for 7- ounces you got yourself a powered glider not just a glider. Pretty cool, huh? Anyway does she thermal? You betcha! I have many flights on the Aspire and have hooked some boomer thermals. When you get in a good one your problem will be how to get down! Be careful diving the Aspire out of a thermal. I have fluttered the wing on two occasions. The best method tested so far is a fairly tight descending spiral. An alternative is to run the motor at half throttle or less to get the big prop blades to create drag. I have not tried this at altitude, but I have used this technique for slowing the plane on landings.

I am really happy with my modified Aspire EP. Even with the stock power system in the garbage it is still an average to good value at $130.00. I never did fly the plane with the stock setup so I can't say for sure that it is a slug. I can say that I am disappointed in Horizon for giving conflicting information on their website and tech support channels. Also, their recommended charger and batteries are not what I consider to be good equipment for the beginning E-flyer. I have returned these items to Horizon. What I can say is that my plane is a great performer and I am very glad that I made the modifications that I did.

Best of luck with your Aspire EP!

Aspire Chronology:

8/26/01 - Update of thermal-ing record: 2-20. I have about twenty flights on the Aspire EP now and have managed to snag a total of two good thermals. I have not been flying in great thermal conditions so I am happy with that poor record. I was more concerned with a sudden loss of power after about ten flights. After extensive debugging the motor was found to be faulty. It was exchange at Joe's Hobbies for a new motor. Just for comparison, you should be getting about 5800 rpm static for an initial rpm. It will then taper down to around 5600 rpm and stay there until the pack starts to die. Current draw on the old motor was 16 amps static with a predicted 14 amp draw in flight.

9/9/01 - An additional cell was added to the battery pack to get the power back. I am very disappointed in the power degradation of the Graupner motor. Right now I think that I am pushing the motor and batteries to the limit. The motor is rated for eight cells and I am using nine. The KR600AE cells have a declining discharge curve at the currents that I am drawing from them. If I had to do it all over again, I think that I would go with a larger motor - perhaps a geared 600 or a brushless DC - and batteries that can handle the higher discharge rates. The airframe is designed to take the extra weight, and I think it would be preferred to be able to get to thermal altitude in 30 seconds compared to 60 or more seconds.

9/11/01 - The power output, even with the added cell, is just barely acceptable. A motor run of at least one-minute is needed to get to thermal altitude. Tonight, in dead-calm air, only two good climbs were possible on a charge. I used to get three. I intend to replace this power system.

10/26/01 - The power system has been replaced with a Speed 600 setup and this website updated to reflect the change. The s600 power package provides a better climb than the s480 did on its best day. The current consumption appears to be only slightly higher than the s480. I have four flights on the s600 system and have found that the motor will barely get warm during a flight. The batteries get hotter than they used to during a two-minute bench test run. In the air, however, there is a longer respite between runs and they are usually just slightly warm by the time the glider lands. The model is currently balanced at the forward most CG location. This makes it noticeably faster and more stable, especially in its ability to penetrate into the wind. The weight has gone up by 4-oz over the s480 system. This has had no effect on the glide; in fact, dead air duration has increased. The KR600AEs are definitely not the optimal cell for this motor. At the present current draw, the KR600AE's have decidedly declining voltage curve during discharge. I will be purchasing an 8-cell pack of Sanyo CP1300SCR cells as a test. The CPs will hold their voltage up at much higher current drains than the AE's. The extra weight of this pack will necessitate its relocation to the "stock" location under the wing to get a CG within limits. The experts on Ezone indicate that the CP cells will give me more power as well as duration - even with one less cell. I am looking forward to it!

4/6/02 - Set a new record duration today! I was up 32 minutes as I hopped from thermal to thermal. I landed with 30 seconds of motor to spare. I could have stayed up longer, but I consider 30 minutes to be "max" and am usually ready for a rest.

4/14/02 - The Aspire airframe and power plant have remained bullet-proof. The Speed Gear 600 motor is barely getting warm and should last a long time. I have become aware of several twists and warps in the Aspire wing and plan on adjusting with a twist and a blast from the heat gun.

5/25/02 - The Aspire now has new batteries! I have converted to the new Sanyo CP1300SCR cells. I had two packs of 8 cells made. My battery charger will charge the new cells in the same or less time than the KR600AE cells despite having more than twice the capacity! There is no longer need for a third pack. The batteries barely get warm and the duration is amazing. I have had to re-write all of my duration records because I can get 15-20 minutes in dead air now. Regardless of the quality of lift, the second pack is charged and ready to go by the time I land my first flight. I have updated the construction photos to show the installation of the new cells.