The TH-57 Perpetual Motion Machine

[Gatordev]

Thread jack~ oh wait, maybe thread back to track:

Sometimes flying the ~57 at night, IMC, over water, I think to myself- damn, one engine. Sweet!

But one REALLY good engine.

When I was flying the T-34 over to the Bahamas for range duty, a friend of the family who's been flying since he was 15 (he's in his 60's now) voiced concern about making the trip from PBI to Nassau in one leg with a single engine. He's a smart pilot with all kinds of knowledge (both as an A&P as well as a pilot), but he just hasn't been exposed, first hand, to the reliability of the PT-6 (or Allison) or to how we operate in general, over water as a Naval Service (I mean everyone...Navy, CG, Marines).

Ironically, this is the same guy, a year or so later, that helped a well-known female aviator take her Mooney from the US to the Azores in record time (as in she was trying for a record). So he obviously got over his SE "liability" fear.

 

[Brett327]

But one REALLY good engine.

When I was flying the T-34 over to the Bahamas for range duty, a friend of the family who's been flying since he was 15 (he's in his 60's now) voiced concern about making the trip from PBI to Nassau in one leg with a single engine. He's a smart pilot with all kinds of knowledge (both as an A&P as well as a pilot), but he just hasn't been exposed, first hand, to the reliability of the PT-6 (or Allison) or to how we operate in general, over water as a Naval Service (I mean everyone...Navy, CG, Marines).

Ironically, this is the same guy, a year or so later, that helped a well-known female aviator take her Mooney from the US to the Azores in record time (as in she was trying for a record). So he obviously got over his SE "liability" fear.

Wow. That's an adventure right there. Is there anything between Bermuda and the Azores?

 

[helolumpy]

Wow. That's an adventure right there. Is there anything between Bermuda and the Azores?

Sharks?

 

[Gatordev]

Wow. That's an adventure right there. Is there anything between Bermuda and the Azores?

I probably need to read up on this trip as I'm sure it's published somewhere, but I think they may have stopped off at one of the "-lands" along the way. I'm thinking both Ice and Green, but I'm not sure. Still, a pretty interesting trip.

 

[PropAddict]

I think they may have stopped off at one of the "-lands" along the way. I'm thinking both Ice and Green, but I'm not sure. Still, a pretty interesting trip.

AOPA had an article a few months back about a couple who took a Cessna (172, IIRC) across the pond, with a deck hit for gas in Greenland. Flying single engine in the tropics is cake compared to that.

 

[phrogpilot73]

I probably need to read up on this trip as I'm sure it's published somewhere, but I think they may have stopped off at one of the "-lands" along the way. I'm thinking both Ice and Green, but I'm not sure. Still, a pretty interesting trip.

Here's a write up by a couple from Switzerland that spent a year long sabbatical in California. They flew from California back to Switzerland with their Mooney, via Newfoundland. Apparently, their Mooney can cruise for 11 hours - but because of Canadian rules, they had to have 3 hours of reserve and the route would give them only 2 hours of reserve. SO, they installed an extra fuel tank in the back seat. Apparently, Newfoundland is the closest spot to the Azores when coming from North America.

 

[Gatordev]

Here's a write up by a couple from Switzerland that spent a year long sabbatical in California. They flew from California back to Switzerland with their Mooney, via Newfoundland. Apparently, their Mooney can cruise for 11 hours - but because of Canadian rules, they had to have 3 hours of reserve and the route would give them only 2 hours of reserve. SO, they installed an extra fuel tank in the back seat. Apparently, Newfoundland is the closest spot to the Azores when coming from North America.

Newfoundland does sound familiar, now that you mention it. And she had done the same thing...putting a big bladder in the back. No matter how you make it happen, that's a long time in a tiny Mooney.

 

[AGonxAV8R]

To clarify, the delay is actually in the depressurization valve. The electrical relays and #2 logic module determine when the depressurization valve should stay open for 3-5 seconds, allowing the backup pump to come online and to protect the current limiters when neither main generator is online.

Regarding the transfer module, what you said is mostly true. However, the transfer to the #2 T/R servo happens a little differently, since it operates independently of the secondary shuttoff of the #1 transfer module (which is the #1 T/R shutoff). If you remember, the #2 T/R servo is on the deck of the hydraulics bay aft of the primary servos and to the right of centerline. It is totally separate from the utility module and the #1 transfer module.

Time delay has to do mostly with the current limiters allowing the A/C motor to draw less juice while spooling up. It takes 4 secs on APU and 0.5 with either main gen online.

The #1 Transfer Valve (Inside the #1 Transfer Module) will start to open at about 2000 PSI or so when #1 Hyd Pump cannot supply press. It will only pressurize #1 Pri Servos and #1 T/R Servo using the B/U Pump. #2 T/R servo can be activated , but it does not go through the #1 Transfer Module. It is routed to the #2 T/R servo Shut Off Valve, which is the one you mention and I have it shown in bold. The actual #2 T/R Servo is right next to the #1 T/R Servo at the TGB. The #2 T/R Servo line Ts off after the Utility Module of the same line supplying to the #1 Transfer Module.

 

[HAL Pilot]

Time delay has to do mostly with the current limiters allowing the A/C motor to draw less juice while spooling up. It takes 4 secs on APU and 0.5 with either main gen online.

The #1 Transfer Valve (Inside the #1 Transfer Module) will start to open at about 2000 PSI or so when #1 Hyd Pump cannot supply press. It will only pressurize #1 Pri Servos and #1 T/R Servo using the B/U Pump. #2 T/R servo can be activated , but it does not go through the #1 Transfer Module. It is routed to the #2 T/R servo Shut Off Valve, which is the one you mention and I have it shown in bold. The actual #2 T/R Servo is right next to the #1 T/R Servo at the TGB. The #2 T/R Servo line Ts off after the Utility Module of the same line supplying to the #1 Transfer Module.

 

[RobLyman]

Time delay has to do mostly with the current limiters allowing the A/C motor to draw less juice while spooling up. It takes 4 secs on APU and 0.5 with either main gen online.

The #1 Transfer Valve (Inside the #1 Transfer Module) will start to open at about 2000 PSI or so when #1 Hyd Pump cannot supply press. It will only pressurize #1 Pri Servos and #1 T/R Servo using the B/U Pump. #2 T/R servo can be activated , but it does not go through the #1 Transfer Module. It is routed to the #2 T/R servo Shut Off Valve, which is the one you mention and I have it shown in bold. The actual #2 T/R Servo is right next to the #1 T/R Servo at the TGB. The #2 T/R Servo line Ts off after the Utility Module of the same line supplying to the #1 Transfer Module.

Yes..what you said. But to be clear, the switch to #2 T/R servo does not happen through the shuttle (transfer) valve. I am not sure everyone participating in the discussion understood that.

The spec we use in the Army is 3-5 seconds. Since they MAKE everyone count "one thousand one, one thousand two, etc..." EVERYTIME we do the checklist, I've noticed it generally takes closer to 5 seconds.

 

[AGonxAV8R]

Yes..what you said. But to be clear, the switch to #2 T/R servo does not happen through the shuttle (transfer) valve. I am not sure everyone participating in the discussion understood that.

The spec we use in the Army is 3-5 seconds. Since they MAKE everyone count "one thousand one, one thousand two, etc..." EVERYTIME we do the checklist, I've noticed it generally takes closer to 5 seconds.

The servo shut off valve is on the deck of the hydraulics bay aft of the primary servos and to the right of centerline next to the main trans as you previously stated, you just called it the servo.

 

[Gatordev]

Someone has been studying for their -9X.

 

[Pags]

Someone has been studying for their -9X.

Yeah, while this info is kind of neat I can't help but feel that it's kind of in the weeds. While knowledge of this level may be necessary for the Army style maintenance method, it seems kind of contrary to the Navy's method. At some point as a HAC or an FCP you just kind of need to know how to tell it's not working (ie, should come on in 3-5sec, came on in 10sec, checks bad). Me knowing all this info doesn't help when it comes time for the troubleshooters to follow the IETMs tree. At some point, I just cut the MAF, be available to answer questions about it and let the desk and the Sailors do their thing, and be ready to op-check it when they're done.

I know this whole line of thought is probably contrary to a lot of peoples' need to have an excrutiatingly in-depth knowledge of NATOPS, but I just can't see what a lot of this helps with other than impressing the NIs of the HC and HSL world.

 

[RobLyman]

The servo shut off valve is on the deck of the hydraulics bay aft of the primary servos and to the right of centerline next to the main trans as you previously stated, you just called it the servo.

Really? OK..I get it...I called it the S E R V O when I meant to say S E R V O S H U T O F F.

 

[AGonxAV8R]

Yeah, while this info is kind of neat I can't help but feel that it's kind of in the weeds. While knowledge of this level may be necessary for the Army style maintenance method, it seems kind of contrary to the Navy's method. At some point as a HAC or an FCP you just kind of need to know how to tell it's not working (ie, should come on in 3-5sec, came on in 10sec, checks bad). Me knowing all this info doesn't help when it comes time for the troubleshooters to follow the IETMs tree. At some point, I just cut the MAF, be available to answer questions about it and let the desk and the Sailors do their thing, and be ready to op-check it when they're done.

I know this whole line of thought is probably contrary to a lot of peoples' need to have an excrutiatingly in-depth knowledge of NATOPS, but I just can't see what a lot of this helps with other than impressing the NIs of the HC and HSL world.

I was once told by a very knowledgeable/wise man that while knowing NATOPS is great, but knowing how to flight/fight the A/C is what matters the most. I actually enjoy knowing the systems. I enjoying knowing how it works. It is not a hassle to me. Sometimes it does bites me in the rear end.

The other day, the maintainer that came to service the hydraulic system kindly asked if he was servicing the system properly as he was adding fluid to the wrong reservoir and I kindly told him to stop. Little things like this is where a bit of knowledge about the system helps.