No ballast on my M20K 252, maybe required...

[turbotrk]

Hi, I am a bit concerned about the CG of my 252, making the calculations with 2 peaple on board is almost out of forward limit.

When landing requires max trim up and with peaple sitting at the back much better. I have noticed looking at the elevator in cruise flight that the leading edge is facing downwards quite a bit, this should create drag, in fact flying with passengers at the back seems to increase my cruise speed. My plane is full of instrumentation, with three blade prop and two alternators. Just to make it a bit worse installing new led lights  I removed flasher box from the tail wich is pretty much on the most aft position and weights a couple of pounds.

looking on the equipment list none of the three ballast options is marked, so I presume to have no ballast at all, and istalling some I should have a much better handling aircraft and on some cases even better cruise performancde due to less drug from the elevator.

Any suggestion?

[turbotrk]

Posting two pictures of the balance chart.

In the first actual situation with two avarage men on board and 22 pounds bag at the back.

In the second same situation but with fixed ballast of 13 pounds at 197.5 inches.

[Guest]

You can get lead shot from a hunting supplier. It comes in a heavy canvas bag, about 25 pound each.  I fly with several in my baggage compartment.   The nice thing is they are not permanent.

Clarence

[aviatoreb]

The Mooney rocket is even more nose heavy - although I had all the 19lbs of ballast (still do).  I cured the problem recently  by trading props for an MT that saved over 30lbs of the nose and dramatically changed the weight envelope.

That said - ballast is quick and easy.

I used to carry a 50lb bag of weights as well to put in the luggage area for just this reason too.

[turbotrk]

I just did a bit of research and found out that my plane afer repainting and avionics installation went for weighting and the CG went from 43.5in at 2091lb to 42.5 at 2200lb. Looking at the maintenance manual it states clearly that for the a/c to be released you need to keep the CG within a certain limit by installing fixed ballasts (charlie weights). They give 4 options: 

no ballast

6lbs

13lbs

20 lbs

On my plane 20lbs was required but the GENIUS maintenance guy released it without doing anything. That's why unless someone is sitting at the back I am always out of envelope so at least 60-80lbs are required to balance it.

[ArtVandelay]

For those with needing ballast, is it possible to move the battery box further aft, seems like that would solve the problem without the extra weight?

[FlyDave]

A friend of mine with a C205 which has a horribly forward CG used to carry either 5 or 10 gallon (I don't remember which) water jugs in the baggage compartment. His thought was it is more versatile. If you need to fill the plane up with useful load you can empty the water jugs for a leg and fill them up for the next. just another option.

[aviatoreb]

I don't remember the exact numbers, but the fixed ballast station is at roughly 196'' and the battery station at 110'' and the baggage station at 95'' so there is a weight savings to carry less ballast at the ballast station way back in the tail for the same change of CG versus a weight in the baggage.

[KSMooniac]

Plus there isn't an existing provision to relocate the battery further aft as far as I know, so you'd have to add structure via 337 with DER input since it is significant.  

Optimal solution is an MT prop upgrade (weight off the nose, less overall empty weight) followed by adding Charlie weights (least amount of added weight to move CG aft).

Carry gallons of water in the baggage area is a good "temporary" solution as mentioned above.

[turbotrk]

Yes , for me at the moment best option is to put 19 pounds charlie weights at station 197.5, max momentum for minimum weight. Just asked for quotation at lasaar, don't think I am going to find anything in europe.

[Seth]

For those with needing ballast, is it possible to move the battery box further aft, seems like that would solve the problem without the extra weight?

That's what Rocket did for the Missile and Rocket conversions rather than just put in charlie weights.  They also added a second battery so there would be use out of those weights.  They created a rack that slides aft after you've installed the battery.  I'm sure some sort of STC could be made, or contact rocket, and see if you can modify, or bring your plane to be modified just with that change.  My guess is they'll price it so high that no one will take them up on it, as they probably want to concentrate on turbine conversions and not on Mooney's anymore.

 

-Seth

[carusoam]

Long Body WNB theory....

The O has a pair of batteries and a stack of Charlie weights, and room for an O2 system and a FIKI system in the back.

If you go with a GTN up front, some boxes like the transponder and audio panel can be remoted to the back.

Using a W&B program and temporary weights is a great way to determine how much ballast works best for your situation.  Then get the correct Charlie weights.  If your trim is maxed out on final approach, you probably want a little more weight in the back.

In line with Erik's logic, the TopProp is available in three weights.  Thick durable blades, thin lightweight blades, and composite...

The four options of different weight CWs are what is available from Mooney.  Your mechanic may need to stack a few back there to get the balance just right.

Best regards,

-a-

 

Edited October 22, 2015 by carusoam

[Guest]

Yes , for me at the moment best option is to put 19 pounds charlie weights at station 197.5, max momentum for minimum weight. Just asked for quotation at lasaar, don't think I am going to find anything in europe.

You can cast your own lead weights quite easily.  Go to your local tire shop and ask for old balance weights.  You will have to build a mould of the correct shape.  Melt the lead in an old sauce pot on an outdoor camp stove and pour it into your mould.  Shipping lead anywhere will be costly.

Clarence

[turbotrk]

I tought about that but Italian caa would probably not agree with such procedure unless mooney will authorize me to do so.

I will try to ask them anyway.

[jetdriven]

Where can we get these Charlie weights? 

[KSMooniac]

Factory parts for the K. I don't think our J's have provisions to add them. Dunno if they can be added easily in a completed tailcone.

Sent from my VS985 4G using Tapatalk

[carusoam]

They have Mooney part numbers in the WNB section of the R's POH.

Let me know if you need help with the POH data I have.

Best regards,

-a

Edited October 24, 2015 by carusoam

[turbotrk]

Had a reply from mooney factory, charlie weights are available, already ordered!

[turbotrk]

Charlie weights finally installed!

According to Mooney lead is very expensive!

[jetdriven]

I'm still interested in putting these in a 201. What was the cost of These Charlie weights 

[M016576]

1 hour ago, jetdriven said:

I'm still interested in putting these in a 201. What was the cost of These Charlie weights 

Me too.

[turbotrk]

They cost around 500$, it depends on how much weight you need. I needed 19lbs (max possible) so I had to buy the 505 wich is made of three weights. Other options are 503 13lbs and 501 6lbs. Now I don't need to trim full nose up on landing and gained 3-4 kts IAS on cruise, the elevator is almost alligned with 2 peaple sitting at the front. Follow the graph on the AFM and if you comply with it you will surely find a great improvement, unless yours is already well balanced.

[carusoam]

Nice report TT,

Thanks for the follow-up.

Best regards,

-a-

[cliffy]

Nice photos of how it's done. Good job

[Moussedded essaid]

On 10/22/2015 at 4:38 PM, FlyDave said:

A friend of mine with a C205 which has a horribly forward CG used to carry either 5 or 10 gallon (I don't remember which) water jugs in the baggage compartment. His thought was it is more versatile. If you need to fill the plane up with useful load you can empty the water jugs for a leg and fill them up for the next. just another option.