Pinecone

I am looking to purchase a Mooney. Looking at a 252 Should I be worried about a mid-time engine (800 - 1000 hours)? Will it likely need some serious work soon? I was just reading Mike Busch about running his Lycomings to some 3000 hours, but have also read that Continental TSIO-360s are expected to need a top overhaul midway to TBO. Thanks

High discharge rate batteries have been around for years. I used to fly RC airplanes and helicopters. 30C rate batteries were the norm. That is, they would support a discharge rate 30 times their capacity. So that 20 KWH pack would be capable of delivering 600 KW, or 800 HP. And 40C and 50C batteries were available. But, high charge rates, high discharge rates, and fully charging/discharging all reduce the battery life. The first two are a function of heat. High rates increase battery heat and heat reduces life. Cell phones charge at 1C or less (1 hour charge time) to increase life. Of course, discharge rates are low. Also, they typically only charge to 80% of full capacity and go into low power mode at 20% remaining. So, for long life, you really only use 60% of the pack capacity. So that 20 KWH pack is only delivering 12 KWH if you want long life. The way that lithium batteries charge is a constant amperage - contact voltage regime. So that from low charge to about 80% charged, they charge at a constant amperage. For the 30C packs, that is typically a max of 3C. So a 2100 mAH pack, would charge at constant amperage of 6 amps to 80%. At that point, the voltage to charge at that rate is 4.2 volts per cell. The charger holds that voltage and the amperage reduces at the pack reaches fully charged. The reason you need to replace the cells after a while is, they wear out. Just like your cell phone, if you keep if for a number of years, the battery life goes down, so you replace it.

https://gami.com/articles/baconsbonus.php Here are some photos taken in an Aerostar where one engine was running LOP and one running ROP. Both making the same power (no yaw). 4.5 - 4.6 GPH less fuel flow LOP. With NA engine, you run into the issue where you need to run ROP for the power to get the speed. If you read Deakin's Pelican Perch articles on AVWEB, he points this out.

I did some research last winter. Both Continental and Lycoming recommend preheating if the temperature is below 20F. And that the engine has sat for several hours (I seem to remember 4). Interestingly, Continental recommends against full time pre-heating.

The problem with using dry ice is that these systems circulate the water that is in contact with the cold source in an open loop The water is pushed through the radiator, then dumped back into the bath. If you use dry ice, the bath and thus the circulating fluid freezes.. One solution would be to not put only water in the unit, but an antifreeze solution. I would use one of the propylene glycol ones that are used to protect potable water systems. The dry ice sublimates to a gas, and does not dilute the antifreeze solution. And with this setup, you could also use freezer packs interchangeably. Water ice could be used, but then you would have to empty out the antifreeze, as it would be diluted and no longer prevent freezing. Or do like race car driver cooling systems, don't cool the air, cool the person. They circulate the cold water through tubing sewn to a t-shirt and cool just the person.

Not particularly. Yes, spending time at higher altitude does increase the body's ability to deal with lower O2 levels. Or, in the case of athletes, training and lower pressure/O2 levels, enhances performance at sea level.

If you fly at altitudes that need O2, it would be a GOOD idea to do an altitude ride. I think the FAA still does them, but you have to go to OKC to do them. Each person has their own hypoxia symptoms and tolerance. And, as has been mentioned, it can change from day to day. I did my chamber rides in the USAF. When we did the hypoxia demo, I outlasted the patience of the instructors. I was going well, not great, but functioning for over 5 minutes, maybe 10. They gave up. Years later I was flying with a couple of friends, both pilots. I was left seat as CFII/Safety pilot. Right seat was under the hood. We were VFR (IFR current, but without current charts) and had to climb to 13.5 for weather (less than 30 minutes) I noticed the guy under the hood stat bobbing around. I looked back, and the guy in the back was OUT. I was fine.