TH-57B Limits

[IKE]

Made this today on watch, posting it so I can get it to my home computer.

Free to use...

 

[jamnww]

Thats awesome man and I am sure they will help you a lot, but there are more comprehensive sheets floating around the squadrons with all the limits in a similar format as the sheets from Primary. Good on you though

 

[BurghGuy]

Personally I always like to type the stuff myself, it helps me to remember it better than reading. But that seems like it took a long time to get the formatting, so good on you.

 

[Flying Low]

This part is wrong.

Torque continuous 85% Military 100% 5 minutes Transient 100-110% 5 seconds
TRQ flashes 1/sec if above 100% flashes 2/sec if overtorque or < 5%

Flashes 2/sec if overtorque or longer then 5 seconds. You just put % instead of seconds.

 

[IKE]

Personally I always like to type the stuff myself, it helps me to remember it better than reading.

I feel the same, it's why I typed this up instead of just using the info on MarineGouge.com. I'll look at gouge to make sure I didn't miss anything, but I never trust it without verification.

This part is wrong.

Torque continuous 85% Military 100% 5 minutes Transient 100-110% 5 seconds
TRQ flashes 1/sec if above 100% flashes 2/sec if overtorque or < 5%

Flashes 2/sec if overtorque or longer then 5 seconds. You just put % instead of seconds.

It flashes twice per second if the torque drops below 5% also.
(NATOPS Page 2-4, last paragraph)

I didn't realize people would actually read this post. I was just typing this up while on watch and had no other way to transfer it to my home PC, since CNET won't let us use web-based e-mail. It's not finished, but if anyone wants, I can repost it when it is.

 

[Flying Low]

I thought you were just mixing up the TRQ numbers. Over 110 or over 100 for longer then 5 seconds.

 

[IKE]

I'm unable to find in the NATOPs what exactly causes the GEN FAIL or MAIN GEN FAILURE lights to illuminate. I imagine it's either the reverse current to the battery, or the zero load. Does anyone know?

I'm similarly unable to find what causes the STBY GEN FAIL, STBY BATT ON, and FCS OFF lights illuminate.

Here's the final draft of my limit sheet if anyone wants it. I had the DA vs. Gross weight and Height-Velocity charts on it, but removed them due to AirWarriors' upload size limit.

 

[insanebikerboy]

I'm unable to find in the NATOPs what exactly causes the GEN FAIL or MAIN GEN FAILURE lights to illuminate.....

It's usually a failure of the generator that would cause a GEN FAIL light to illuminate.....

 

[jamnww]

I'm similarly unable to find what causes the STBY GEN FAIL, STBY BATT ON, and FCS OFF lights illuminate.

STBY GEN FAIL - no kidding the standby gen fails.
STBY BATT ON - standby battery is being drained or at least the recharge wiring has failed meaning that the standby battery will no longer be recharged, and could be drained.
FCS OFF - the IP turned off the AFCS...

 

[IKE]

It's usually a failure of the generator that would cause a GEN FAIL light to illuminate.....

I'm unable to find in the NATOPs what exactly causes the GEN FAIL or MAIN GEN FAILURE lights to illuminate. I imagine it's either the reverse current to the battery, or the zero load. Does anyone know?

Thanks for the help. What I meant was: is it a voltage drop, current drop, current reversal, or something else?

Same with the other failures. I'm sure I'll have to go ask a maintenance tech and/or look at an electrical schematic, because most SNAs are "I Believe" (i.e. "Is it on the test? If not, I don't care. Just let me fly") button-pushers.

 

[MasterBates]

You should go HSM/HSL :icon_smil

 

[ArkhamAsylum]

I think the STBY BATT light goes on if the stby batt stays on after the battery/generators are off (i.e. you shut down but forget the stby batt). Also, make sure you correctly understand the Batt Relay light when you get to the Charlies, as many guys do not fully grasp the concept.

 

[insanebikerboy]

Thanks for the help. What I meant was: is it a voltage drop, current drop, current reversal, or something else?

Same with the other failures. I'm sure I'll have to go ask a maintenance tech and/or look at an electrical schematic, because most SNAs are "I Believe" (i.e. "Is it on the test? If not, I don't care. Just let me fly") button-pushers.

Yeah, although I was trying to be a smart ass, the light will illuminate when the generator stops working well enough to stay online. While it could be a total failure or just a partial, once the voltage gets low enough the reverse current relay cuts the generator out of the loop. Generator failure could mean total failure (produces 0 volts) or something above 0. Considering it's the same starter/generator as the T-34, I'm gonna hazard a guess that it's 27 volts it gets cut out at.

 

[jamnww]

Thanks for the help. What I meant was: is it a voltage drop, current drop, current reversal, or something else?

Same with the other failures. I'm sure I'll have to go ask a maintenance tech and/or look at an electrical schematic, because most SNAs are "I Believe" (i.e. "Is it on the test? If not, I don't care. Just let me fly") button-pushers.

I would have to disagree on this one, find different SNAs to talk to, ask around, someone has to know.

As far as the STBY BATT, .... (REF: P-402 TH-57 Systems Book) look at the schematic on page 9-2 and you will see that the Pilot's Attitude Indicator is powered through the STBY BATT all the time, its just that during normal operation it is recharged by the ESS #1 Bus. If the connection between the ESS #1 bus and the STBY BATT becomes interrupted then the STBY BATT will drain regardless of whether there is a Gen failure or not. That being said it is possible for the Pilot Attitude Indicator to fail due to STBY BATT exhaustion with both Gens fully operational.

 

[IKE]

Here's a link to the document with charts and a few corrections (I was 1° off on TOT start limit)

TH-57B/C Limits