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All trips observe a necessary protocol for safety, productivity, and convenience for the owners. Please read and be aware of the following and for those leading trips, please use this as a checklist for trips.
OBJECTIVES:
A sound understanding of the objectives for any trip are fundamental for its success. The cave is big and complex and unless a participant on the trip is well acquainted with your destination in the cave, you will need to do your homework. You may need to gather old trip reports, survey schematics, copies of survey notes, lead lists, etc. Area cartographers can be a great help in this endeavor and may have already prepared "trip packets" of this information for certain objectives. A little planning can mean the difference between a very productive trip and a nominal or even wasted trip. If planning a trip, you will know who to contact for this information; please do so with as much notice as possible (a couple weeks at a minimum).
BEFORE THE TRIP:
1. Get appropriate permission for trip, arrangement for keys, etc. See Access for information about specific caves.
2. Surface Watch arranged. This does not have to be someone at the cave, but someone who knows of your destination, route, and estimated time out of the cave. They will need to be contacted after you leave the cave – a phone call a few hours later is sufficient, but this needs to be discussed and agreed beforehand.
3. Read compass course just prior to heading for the cave.
All survey equipment must be run on one of the local compass courses. As of this writing, the only compass course is at the Maple Springs Research Center in Mammoth Cave National Park. Two more are planned: one, at the Hamilton Valley Property owned by CRF, just east of the park; and, two, on the cave property surrounding the Downey Avenue Entrance. We will let you know when these become available.
Instruments should be read as accurately as possible in both directions. Compass readings should agree, more-or-less exactly. The inclinometer reading may not agree. The compass course is a level course, and if the inclinometer is off the readings will be consistent, although off (e.g., +0.5/+0.5 could be an expected reading for an inclinometer one-half degree off). Both sets of readings and the instrument serial numbers should be noted in the survey book, and the compass course should be run prior to each trip.
The compass course is used to determine the corrections that need to be applied to the specific instruments for the correct bearing and inclination. Seemingly anal, this actually has a lot of impact to how well the cave hooks together. Suunto compasses and inclinometers can be significantly off (one degree for the compass, and one-half degree for the inclinometer are not uncommon). Coupled with the declination drift over time, the compass course is really the only way to manage this.
AT THE CAVE:
1. Compass Course read/recorded in the survey book
2. Leave all gates as you find them; all gates on the Downey Avenue Entrance property must be closed at all times.
3. For the Downey Avenue Entrance, park vehicles either on top of the hill or on the saddle above the trailer. Do not park on the roadway.
4. Sign-in and Sign-out in the book, as appropriate.
IN THE CAVE:
1. Make sure inner air-seal, if available, is closed and secure.
2. Stay on all trails!
Survey:
All survey procedures closely adhere to those as documented in the CRF Personnel Manual, but a synopsis of this is included here.
a) Cover Page: Please ensure that all necessary information is recorded. This includes personnel, compass course description, date, time-in and –out, and location description. This last item is very important to determine where the survey is to be tied. Vague information can lead to a lot of work by the individual entering the data or, worse, passages hung off the wrong station.
b) Survey Designations: This is just an issue of common sense. There is no real problem with whatever survey letter(s) chosen for the designation. Continue existing surveys with the same designation, side surveys should have a different designation. This can be one or two letters and is usually governed by individual teams' style. Try not to use duplicate designations of nearby surveys, this can cause confusion. Also, try to avoid non-sequential numbering (Don't run a B Survey to B70, backtrack to B50 and continue the B series at B71. Start another designation – a C or BA series might be an option). Non-sequential numbering can cause great confusion for those who might use surveys as route-finding tools. Can you imagine the frustration of needing to find station B100 (in the aforementioned example) and finding a dead-end at B70?
c) It is policy that all surveys in the cave are done with foresights and backsights, for both the inclination and azimuth. Be vigilant about this policy, as the numbers of blunders that make it onto the map are high when this is not done. Of course, this is not always practical. Use your common sense on this. It is practice that when a backsight (or foresight) cannot be done, the other reading is read twice, and is done as 'objectively' as possible (for example, resetting body position between shots, alternating redundant readings – e.g., compass, inclination, compass, inclination). Backsights should agree within one degree, unless conditions dictate otherwise.
Try to avoid the common phenomenon of the most recent reading being deemed the correct one. It is not unusual that when readings do not agree, that the instrument reader will 'reread' the reading and the other is rejected. In some survey books, I might observe that for every case of a reading disagreement, the frontsight is always the one rejected. This seems to be a manifestation of not wanting to move to the other station for a re-reading and unawareness that extraneous variables may be involved – poor setup position, poor positioning of the target light, close proximity of a deflective material on the caver due to the setup (e.g., flashlight held to close to the compass), natural deflective material (hematite gravel, etc.). As distasteful as it might be, consider both readings as equally suspect and make the effort to fully resolve – take the time to verify the other reading.
d) Be ever vigilant about the survey. Common problems include the following and can easily be avoided.
Mis-ties: If there is any doubt about the tie, makes note of it in the book. Ancient stations can be easily misread. Furthermore, I know of several tie station errors that are due to the station having been mislabeled in the cave. This is difficult, but can be mitigated by good description and sketch of the junction area – I do try to verify ties against the old book, but any information you can provide is a help.
Reversed Shots: Although not frequent, this is a significant error. Reversed shots are where the shot data is entered incorrectly in the book – frontsight and backsights are interchanged. These are most common near tie stations or where the cave morphology is problematic. This manifests in the rhythm of the survey party being disrupted – readings are provided out of order, duties temporarily rearranged, etc. In such situations, double check everything to make sure it is right. A good sketcher can catch compass reversals; inclinometer reversals are more problematic although a visual validation can catch these. Remember that foresights and backsights in this situation still do match, it is just that they are recorded in the wrong slot (due to error by the note taker or by the person providing the readings).
Junction Sketches: This is the nightmare of every cartographer and seems to be a continuing chronic problem. The beginnings or ends of surveys seem to have a wanting sketch, usually due to the one presuming the other was, or will be, better. I have seen whole stretches of cave with either a poor sketch or, in some situations, no sketch due to this phenomenon. Furthermore, a sketch of a side passage leading off a survey is not usually precise. When surveying into a side passage, take the time to sketch the junction carefully.
Lead Descriptions: No openings in the sketch should be left to the imagination. Any relevant information should be noted, dimensions, distance explored, features (stream passage, piracy canyon, etc.), who checked it, etc. This goes for the end of the survey, also. Vague passage openings on the sketch do little good.
Passage Dimensions: This data is very useful for the map, and should reflect the sketch. An oft-used technique of having passage dimensions provided by someone else to the sketcher usually does not work well – perspectives are usually too different. Also, in complex areas, dimensions for repeatedly used stations should be supplied, and may be different, since the dimensions are relative to the direction of the survey. In large passages, or where dimensions change dramatically (e.g., dome enlargements or junctions), tape the walls. You would be surprised how bad estimating in dynamic passage situations can be.
AFTER THE TRIP:
1. Close all gates, sign-out in the log book (Downey Avenue Entrance)
2. Contact Surface Watch
3. Write a trip report, detailing as much information as possible. Anecdotal is good, as it adds a human factor to the trips, but make sure that leads are described, obstacles, noted, etc.
4. Return notes to Chief of Cartography (Jim Borden). If necessary to do so by mail, please do promptly. Before sending, please make a copy as a backup in the event the notes are lost in the mail.