DG-303 spar issues - puchase?

On Wednesday, May 20, 2020 at 4:43:35 PM UTC-6, Paul wrote:
On Wednesday, May 20, 2020 at 2:58:27 PM UTC-4, Charlie M. (UH & 002 owner/pilot) wrote:
Cost to get info from the mfr. you can do a yearly, or case by case......thus "tax".

Below is what I found on DG's FAQ website (https://www.dg-flugzeugbau.de/en/mai...vice-contract).

Am I reading this incorrectly?

"I own a glider made by your company, which I just purchased second hand. Do I have to conclude a Service Agreement?
No you don’t have to. All gliders built after 1996 by DG Flugzeugbau take advantage of our lifelong after-sales-service. You have virtually purchased it with your used aircraft. The same applies to customers who own such a DG- or LS-glider and want to sell it. The buyer does not have to sign a Service Agreement."

I should let John answer, but as far as I know his 303 is new enough that it qualifies for the lifelong after-sales-service.

I owned a DG-300 for a good while, and really liked it - many memorable flights including the 1000-km task during the Regional contest at New Castle VA. I'd recommend it highly.

Here are two notable details worthy of attention, that seem not to be common knowledge among owners:

The gear-retract handle is a knob on the end of the actuator rod that rotates outboard to lock the gear up or down. Its rotation is restrained by a friction washer. Over time, this wears / compresses, so the friction decreases. It can reach the point where the knob rotates freely, making the gear somewhat prone to collapse, especially when landing on rough ground. The friction is easily adjusted by a nut that compresses the friction washer. Owners should be aware that a freely rotating knob is a problem waiting to happen - but it seems only a minority understand this issue.

The spoiler panels are often just a bit too high at their outboard end. This means that when you pull up and the wings flex, the spoiler box pushes the end of the spoiler up a few mm above the wing surface. You thus suffer a small performance loss each time you pull into a thermal, and perhaps when you thermal in a steep bank.

The problem is easy to detect: Pull the divebrakes open and inspect the bottom of the box at its outboard end. If it's been pushing on the spoiler panel, you'll see a black mark caused by aluminum rubbing on fiberglass. In my experience, about 60% of DG-300 gliders exhibit this (I have no info on the DG-303). The solution is fairly simple: shave a small wedge of aluminum off the outboard bottom edge of the panel - perhaps 6mm at the end, tapering to nothing over a distance of 80mm.

On Saturday, May 23, 2020 at 12:32:56 PM UTC-4, John Good wrote:
I owned a DG-300 for a good while, and really liked it - many memorable flights including the 1000-km task during the Regional contest at New Castle VA. I'd recommend it highly.

Here are two notable details worthy of attention, that seem not to be common knowledge among owners:

The gear-retract handle is a knob on the end of the actuator rod that rotates outboard to lock the gear up or down. Its rotation is restrained by a friction washer. Over time, this wears / compresses, so the friction decreases. It can reach the point where the knob rotates freely, making the gear somewhat prone to collapse, especially when landing on rough ground. The friction is easily adjusted by a nut that compresses the friction washer. Owners should be aware that a freely rotating knob is a problem waiting to happen - but it seems only a minority understand this issue.

The spoiler panels are often just a bit too high at their outboard end. This means that when you pull up and the wings flex, the spoiler box pushes the end of the spoiler up a few mm above the wing surface. You thus suffer a small performance loss each time you pull into a thermal, and perhaps when you thermal in a steep bank.

The problem is easy to detect: Pull the divebrakes open and inspect the bottom of the box at its outboard end. If it's been pushing on the spoiler panel, you'll see a black mark caused by aluminum rubbing on fiberglass. In my experience, about 60% of DG-300 gliders exhibit this (I have no info on the DG-303). The solution is fairly simple: shave a small wedge of aluminum off the outboard bottom edge of the panel - perhaps 6mm at the end, tapering to nothing over a distance of 80mm.

John, really great information, thank you!

Paul

The gear-retract handle is a knob on the end of the actuator rod that rotates outboard to lock the gear up or down. Its rotation is restrained by a friction washer. Over time, this wears / compresses, so the friction decreases. It can reach the point where the knob rotates freely, making the gear somewhat prone to collapse, especially when landing on rough ground. The friction is easily adjusted by a nut that compresses the friction washer.. Owners should be aware that a freely rotating knob is a problem waiting to happen - but it seems only a minority understand this issue.

Paul

DG also offers a retrofit kit that forces the brakes torque tube in the outboard position. Technical note TN 359/22 (service contract required)

https://www.dg-flugzeugbau.de/en/dow...-22/8FW25e.pdf

DG also offers a retrofit kit that forces the brakes torque tube in the outboard position. Technical note TN 359/22 (service contract required)

https://www.dg-flugzeugbau.de/en/dow...-22/8FW25e.pdf

When I go try DG 400, the DG300 gear fix was already performed on the bird. Simple elegant solution that I would highly recommend.

Kevin
92

My 303 had the gear retract handle problem causing a gear collapse back in 2014. I had the entire bent bracket re-engineered and rebuilt so N303MR will never have a gear collapse again. We joke sometimes that DG stands for "Defective Gear" It's really hard to explain but easy to show and tell. At least I don't have to worry about it failing again on my 303

On Saturday, May 23, 2020 at 1:21:19 PM UTC-4, wrote:
My 303 had the gear retract handle problem causing a gear collapse back in 2014. I had the entire bent bracket re-engineered and rebuilt so N303MR will never have a gear collapse again. We joke sometimes that DG stands for "Defective Gear" It's really hard to explain but easy to show and tell. At least I don't have to worry about it failing again on my 303

John, what alterations were made? Also, I have been reading the TNs, and I'm confused if simple aerobatics, i.e. loops, chandelles, etc., are allowed or not.

Paul

Paul,
I had my gear lock bracket lengthened an inch so that the gear handle does not give a false lock in front of the bracket and not behind it as happened in my case when my gear collapsed after I lowered the gear with a false lock. The previous pilot installed the stronger spring installed on the gear handle so it won't pop out on bumpy landing.
I don't think they made it specific differentiation in the TN so I assumed in my favor with a healthy margin of safety that simple aerobatics fall under the utility category and not the aerobatic category as stated in the flight manual. Spins, Inside loop, stall turn, Chandelle, and lazy eight are all considered simple aerobatics flown under the utility category. All of these are low G maneuvers anyway which fall well with in it's capacity of a 303 with a healthy margin of safety even if it had the spar cap problem which most don't even have. I was always too heavy to fly the technical Acro category anyway but all the things I like to do anyway are labeled under utility anyway so I never really cared. My personal feeling is that in the end its mostly a paperwork check the box in the EU to be letter of the law +7G with 1.5 safety margin specs from what I have read. The worst defective spar cap still had a 1.4 safety margin on the +7g rating. Most gliders are rated at +5g's. It broke at over +9g's when they tested it. The FAA never cared and we never got an AD in the USA from it as no plane ever suffered a failure in over 20 years. Just my 2 cents.

On Tuesday, May 26, 2020 at 7:26:43 PM UTC-4, wrote:
Paul,
I had my gear lock bracket lengthened an inch so that the gear handle does not give a false lock in front of the bracket and not behind it as happened in my case when my gear collapsed after I lowered the gear with a false lock. The previous pilot installed the stronger spring installed on the gear handle so it won't pop out on bumpy landing.
I don't think they made it specific differentiation in the TN so I assumed in my favor with a healthy margin of safety that simple aerobatics fall under the utility category and not the aerobatic category as stated in the flight manual. Spins, Inside loop, stall turn, Chandelle, and lazy eight are all considered simple aerobatics flown under the utility category. All of these are low G maneuvers anyway which fall well with in it's capacity of a 303 with a healthy margin of safety even if it had the spar cap problem which most don't even have. I was always too heavy to fly the technical Acro category anyway but all the things I like to do anyway are labeled under utility anyway so I never really cared. My personal feeling is that in the end its mostly a paperwork check the box in the EU to be letter of the law +7G with 1.5 safety margin specs from what I have read. The worst defective spar cap still had a 1.4 safety margin on the +7g rating. Most gliders are rated at +5g's. It broke at over +9g's when they tested it. The FAA never cared and we never got an AD in the USA from it as no plane ever suffered a failure in over 20 years. Just my 2 cents.

Thanks John for the answer.

paul

I appreciate the kind words from Mike C. about MQ that I have listed on W&W after well over a decade of flights. I flew it after two-seaters, a 1-26, Libelle and Discus. I think that new glider pilots have some great options in the Discus/DG300/LS4 category with automatic hookups and nice (perhaps read as Cobra) trailers. These ships seem much friendlier to me than other ships new glider pilots get stuck in.

Friendly and Comfortable- I did not fly mine for 18mos and was able to zoom around at 108km/h dry on my first flight for a couple of hours. I love the friendly wing (perhaps read as fat) and the relatively large rudder with outboard aileron positions that make it roll much faster than the Discus. I like the DGs so much that I am hoping to finally step up into another as I planned so many years ago when I thought I should continue to build hours in the DG300 first (perhaps read as not having enough coin).

It seems like there are many options for anyone in the market now. I will not be too sad if this means it will be another decade of flying my DG300. I would like to add some complexity and glide points now that I have added another 500hrs of experience though.