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Phase 1 Hobbs or Tach

jeffmoreau

jeffmoreau

Well Known Member
To satisfy the 40 hours of testing assigned to my aircraft, do I use Hobbs or Tach time?

Please let me know.
 
The 40 hours minimum is the time the aircraft is "in flight" (hence the term "phase I flight testing"). This does not include "ground" time.
 
Tach time is not necessarily flight time.

There are lots of conflicting opinions (even between FSDO's) on when the 40hr minimum is met.

Some count anytime the engine is running, some count hobbs time, some count tach time, some only count in motion time, some only count actual wheels not touching the ground time.

My phase I operating limitations only say "operated for at least 40hrs" or something like that. What does "operated" mean? It means different things to different people.

Take a poll of the 6800+ RV's out there flying and I bet most of them used HOBBS time for meeting their phase I minimums.

For me it did not matter since I was not so much concerned with hitting the 40 so much as I was with testing and making sure my aircraft was ready for phase II.
 
Brantel said:
Take a poll of the 6800+ RV's out there flying and I bet most of them used HOBBS time for meeting their phase I minimums.
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Why would you install a Hobbs meter in an airplane that isn't used for hire? The intent of the Hobbs is essentially to allow flight schools and others who rent out aircraft to charge for the time the airplane sits idling on the ground.

Just curious...

And back to the original question - I used Tach time. My airplane doesn't have a Hobbs.
 
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With my Dynon Skyview, the Hobbs runs any time the RPM is above Zero or there is oil pressure. The tach runs with some consideration of cruise power. I don't think I would install a hobbs if I didn't have Skyview, but since I have it, I used it for Phase I.

My recommendation is that you don't rush ending your phase I. It's likely the only time you'll be in such a "box" and once it's over you'll forget all about it.

I am at about 50 hours hobbs now and have flown a few passengers. Even still I am learning more about the plane.
 
My EMS has both....as do most other if not all EMS's. However if I had went with steam, most likely I would not have installed one.

People love to use Hobbs time when making entries in their logbook........

Next time your on a commuter flight, feel great about that young pilot up front that met a bunch of his minimum hours as pilot in command while sitting on the ground with the engine running.

This might be a better question for all those people that built panels with Hobbs meters that I see in the archives....

Kyle Boatright said:
Why would you install a Hobbs meter in an airplane that isn't used for hire? The intent of the Hobbs is essentially to allow flight schools and others who rent out aircraft to charge for the time the airplane sits idling on the ground.

Just curious...

And back to the original question - I used Tach time. My airplane doesn't have a Hobbs.
Click to expand...
 
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I tracked the flight time, off at xx30 hours, down at xx00 hours until I hit 40 hours or I should say we, I had two very trusted friends helping flyoff the program but the total time in the air was how we knew we had 40, besides if you do a full test program it seemed to take 40 hours although if I was given a 25 hour window we could have accomplished the same thing just with less boring of holes in the sky.:D
 
To answer the question: why install a hobbs?
I used Van's tach which doesn't have a recording
feature. The only hour meter solution I could come
up with was to install a hobbs recording meter
switched on with oil pressure. Is there something
better available considering cost? My hobbs does
read somewhat high.
Tom
 
tomwebster said:
To answer the question: why install a hobbs?
I used Van's tach which doesn't have a recording
feature. The only hour meter solution I could come
up with was to install a hobbs recording meter
switched on with oil pressure. Is there something
better available considering cost? My hobbs does
read somewhat high.
Click to expand...

Same here. No tach.
 
Flight Time

Here is how it is defined, or used to be. I havent checked the FARS lately;
Flight Time = "Pilot time that commences when an aircraft moves under its own power for the purpose of flight and ends when the aircraft comes to rest after landing."
Makes me wonder how you log Glider time as the aircraft never moves under its own power?
 
tach vs hobbs

tach time for oil changes, hobbs time for pilot log book.
sort of like..........
nautical miles for navagation, statue miles per hour,,, for bragging,, it sounds faster :cool:
 
I'd be willing to bet JonJay's definition would hold up in court. I think too many people try to read too much into the regs. Just read what it says, nothing more! Always pay attention to comma's, also.
 
The CAA here in NZ wanted me to use Tacho...my AF3500s have both so it just meant a bit more stick time for my test pilot before I could have a crack! :)
 
David-aviator said:
Jeff, just write down the time you take off and land and record it in a log of some sort.

It is no big deal. No one will ask for a congressional investigation over it.
Click to expand...

I would say write down your "block out" to "Block in" time!!!

You never shortchanged yourself that way at TWA did you David?:D

Best regards,
Jon
 
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